Delicious & Healthy Low Carb Spaghetti Squash Lasagna: Your Ultimate Pasta-Free Comfort Food!
Are you craving the rich, comforting flavors of traditional lasagna but want to skip the heavy carbs and gluten? Look no further! This incredible low carb Spaghetti Squash Lasagna Casserole is your answer. It’s a gluten-free, delightfully low-carb, and surprisingly easy-to-prepare dish that offers all the cheesy, savory goodness you love, without any of the pasta. This healthier twist on a classic favorite is destined to become a beloved weeknight staple in your home.
This Spaghetti Squash Lasagna recipe has been a longtime favorite among our readers, consistently converting even the most skeptical into true believers of spaghetti squash’s versatility. It’s one of the earliest recipes from our blog’s humble beginnings, yet it’s a dish I find myself returning to time and time again, always with immense satisfaction.
While I certainly appreciate a classic pasta dinner, I genuinely do not miss the traditional noodles in this particular lasagna. It absolutely rivals my favorite pasta dishes, bursting with all the essential “good stuff” that makes lasagna so irresistible: savory and flavorful Italian chicken sausage, a rich and creamy ricotta cheese layer, and perfectly golden, toasty mozzarella. The brilliant substitution here is using tender, cooked spaghetti squash strands in place of traditional lasagna noodles, offering a lighter, nutrient-dense foundation for this hearty meal.
It’s the ultimate comfort food recipe, perfect for warming you up on a chilly evening, while also ensuring you get a healthy dose of daily vegetables. This dish proves that healthy eating doesn’t mean sacrificing flavor or satisfaction!
If you’re exploring more delicious low carb lasagna options, be sure to check out our equally fantastic noodle-less Zucchini Lasagna Recipe!
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Why You Will Love this Spaghetti Squash Lasagna Recipe
This isn’t just another spaghetti squash recipe; it’s a culinary experience designed to delight your taste buds while keeping your health goals on track. Here’s why this low-carb spaghetti squash lasagna will quickly become a cherished favorite:
- Authentic Lasagna Experience, Minus the Carbs: Savor all the deeply satisfying flavors, creamy textures, and cheesy layers you expect from classic lasagna, but without the heavy carbohydrate load of traditional pasta. It’s a guilt-free indulgence that doesn’t compromise on taste.
- Hearty, Satisfying Portions: Despite being low-carb, this lasagna delivers a substantial and filling meal. Each generous portion is designed to keep you feeling full and completely satisfied, preventing those unwelcome post-meal cravings.
- Packed with Nutrients and Macro-Friendly: This recipe is a nutritional powerhouse! It’s brimming with lean protein from the chicken sausage, fiber from the spaghetti squash and vegetables, and healthy fats from the cheeses and olive oil. This makes it a fantastic option for various dietary preferences, including Keto-friendly, and compatible with programs like 21 Day Fix and Weight Watchers (WW).
- Ideal for Easy Weeknight Meals & Meal Prep: Its straightforward preparation makes it perfect for a busy weeknight. Even better, this lasagna is a meal prep superstar! The flavors meld and deepen overnight, meaning leftovers taste even more delicious and are ready for quick reheating throughout the week.
- Highly Customizable to Your Liking: This recipe offers fantastic flexibility. Easily adjust the fillings to suit your family’s preferences. Feel free to incorporate additional vegetables for an extra nutrient boost or swap in your favorite protein to make it uniquely yours. It’s a versatile canvas for your culinary creativity!
Key Ingredients for Your Spaghetti Squash Lasagna
Crafting this delicious, noodle-less lasagna requires a selection of fresh, high-quality ingredients that come together to create a symphony of flavors. For the precise measurements and complete details, please refer to the comprehensive recipe card located at the bottom of this post.
Here’s a closer look at what you’ll need to make this incredible dish:
Olive oil cooking spray: While you can certainly use a tablespoon or two of olive oil, I personally love using my EVO spray to minimize the amount of added oil, making the dish even lighter.
Spicy Italian Chicken Sausage or Turkey Sausage: This is where much of the savory flavor comes from. I often prepare my own homemade chicken sausage using ground chicken for better control over ingredients, but a high-quality store-bought spicy Italian turkey or chicken sausage works perfectly as well.
Onion: Yellow or white onion varieties are best for their balanced flavor, providing an aromatic base for the meat sauce.
Garlic: Freshly minced garlic adds an unparalleled depth of flavor. If fresh isn’t available, a good quality garlic powder can be substituted, though fresh is highly recommended.
Part-skim ricotta cheese: This creates the creamy, rich layer essential to any lasagna. For a protein boost, cottage cheese is an excellent alternative. If you’re looking for a dairy-free option, plant-based vegan ricotta can be used.
Egg: A single egg acts as a binder, helping the ricotta mixture hold its shape and prevent it from becoming too runny. If you have an egg allergy, you can omit it, but the mixture might be slightly less firm.
Homemade tomato sauce: A flavorful, no-sugar-added tomato sauce is crucial. My homemade recipe is fantastic, but if you’re short on time, a high-quality jarred marinara sauce like Rao’s is a superb choice.
Cooked spaghetti squash: The star of our low-carb lasagna! You’ll need a medium-sized squash, which typically yields about 4 cups of cooked “noodles.” Ensure it’s properly prepared to avoid excess moisture.
Mozzarella cheese: Freshly shredded mozzarella melts beautifully and provides that classic gooey, stretchy cheese pull. Pre-shredded works, but fresh often yields better results.
Parmesan cheese: A sprinkle of freshly grated Parmesan adds a sharp, salty punch of umami, elevating the overall flavor profile.
Fresh basil: The vibrant aroma and fresh taste of basil are key to finishing this dish. If fresh basil isn’t on hand, you can substitute with about 1/2 teaspoon of dried basil.
Salt and pepper: Essential for seasoning each component of the lasagna – from the spaghetti squash strands to the ricotta mixture – to ensure a well-balanced and delicious final product.
How to Make Your Delicious Spaghetti Squash Lasagna
Creating this low-carb spaghetti squash lasagna is a straightforward process, broken down into a few manageable steps. You’ll find detailed, printable instructions in the recipe card below, but here’s a comprehensive guide to walk you through each stage:
Step One: Prepare the Spaghetti Squash Foundation
- Cook the Squash: This recipe starts with cooked spaghetti squash, so your first task is to prepare it. There are several effective methods: roasting it in the oven, microwaving it, using your Instant Pot, or even slow cooking it. Each method has its advantages, and I have a dedicated post on how to prep spaghetti squash that offers detailed guidance for perfect results. Aim for a medium squash that yields about 4 cups of cooked strands.
- Extract and Dry the “Noodles”: Once your squash is cooked and has cooled enough to handle, carefully slice it in half, discard the seeds and stringy bits from the center. Then, use a fork to gently scrape out the beautiful, spaghetti-like strands. This is the fun part! To prevent a watery lasagna, it’s crucial to remove excess moisture from the squash. Place the cooked strands in a clean kitchen towel or several layers of paper towels and give it a firm squeeze over your sink or a large bowl. This step is vital for a firm, delicious lasagna.
- Season the Squash: After drying, transfer the spaghetti squash noodles to a bowl and season them simply with a generous sprinkle of salt and freshly ground black pepper. This initial seasoning layer is essential for building overall flavor.
Step Two: Prepare the Flavorful Fillings
- Cook the Meat and Aromatics: Lightly spray a large skillet or cast-iron pan with olive oil cooking spray (or a small amount of olive oil). Place it over medium heat. Add the diced onion and sauté until it becomes translucent and wonderfully aromatic, usually about 5-7 minutes. Next, add your Italian chicken or turkey sausage (casings removed, if applicable) and brown it, breaking it up with a spoon, until it’s fully cooked through. Finally, stir in the minced garlic and cook for just an additional minute until fragrant – be careful not to burn it. Remove the delicious meat and veggie mixture from the heat and set aside.
- Prepare the Creamy Ricotta Mixture: In a medium-sized mixing bowl, combine the part-skim ricotta cheese. Crack in one egg, add the grated Parmesan cheese, and a sprinkle of black pepper. Stir everything together thoroughly until it’s well combined and smooth. The egg helps bind the ricotta, creating a stable, creamy layer in your lasagna.
Step Three: Assemble Your Delicious Lasagna
- Preheat Oven and Prep Dish: Begin by preheating your oven to 350°F (175°C). Lightly spray a standard 9×13 inch casserole dish with olive oil cooking spray. This will prevent sticking and make cleanup easier.
- First Layer – Sauce: Spoon about half of your prepared tomato sauce evenly across the bottom of the casserole dish. This creates a flavorful base and helps prevent the squash from sticking.
- Second Layer – Sausage and Squash: Next, carefully spread the cooked Italian chicken sausage mixture over the sauce. Then, gently layer the seasoned spaghetti squash strands evenly over the sausage. This is your “noodle” layer!
- Third Layer – More Sauce & Basil: Pour the remaining half of the tomato sauce over the spaghetti squash, spreading it to cover as much as possible. Sprinkle a generous amount of fresh chopped basil over this layer, adding a burst of herbaceous flavor.
- Final Layers – Ricotta and Mozzarella: Dollop spoonfuls of the creamy ricotta cheese mixture over the sauce. Use the back of a spoon to gently spread it out, but don’t worry about perfection – a rustic look is fine. Finally, liberally sprinkle the shredded mozzarella cheese over the top, ensuring full coverage for that golden, bubbly crust.
Step Four: Bake to Perfection
- Bake Until Bubbly: Place the assembled lasagna in your preheated oven and bake for approximately 15-20 minutes, or until the cheese is beautifully melted, bubbly, and the edges are lightly golden.
- Achieve Golden Crust (Optional Broiling): For an extra-gorgeous, golden-brown and slightly crispy cheese topping, you can carefully broil the lasagna on low for an additional 5-10 minutes at the very end. Crucially, watch it very carefully during this stage, as cheese can go from perfectly golden to burnt in a matter of seconds!
- Rest and Serve: Once baked, remove the lasagna from the oven and let it rest for a few minutes before serving. This allows the layers to set, making it easier to portion. If you notice any excess water at the bottom of the pan, you can carefully tilt the dish and drain it from a corner, or simply serve with a slotted spoon.
- Garnish: Finish your masterpiece with a final flourish of fresh basil leaves before serving. Enjoy your healthy, delicious, and satisfying low-carb spaghetti squash lasagna!
Clever Substitutions & Creative Variations
One of the best aspects of this spaghetti squash lasagna recipe is its incredible adaptability! Feel free to customize it to perfectly suit your family’s preferences, dietary needs, or simply whatever ingredients you have readily available in your pantry and fridge. Here are some ideas to get you started:
- Protein Power-Ups:
- Instead of Italian chicken sausage, you can easily swap in lean ground beef, ground turkey, or even ground pork. Ensure it’s seasoned well with Italian herbs and spices.
- Have leftover meat sauce from a previous dinner? It’s a fantastic shortcut! Just use it in place of the ground meat and a portion of the tomato sauce.
- Cheesy Alternatives:
- If ricotta cheese isn’t your favorite or you’re looking for an extra protein boost, opt for protein-packed cottage cheese. Its texture will be slightly different, but the flavor is just as delicious.
- For those following a dairy-free or vegan diet, high-quality vegan ricotta and mozzarella alternatives can be used to create a plant-based version.
- Veggie Boost:
- To make this a truly vegetarian lasagna, simply omit the meat entirely. Instead, load it up with extra vegetables! Sautéed spinach (ensure it’s well-drained), mushrooms, bell peppers, zucchini, or even finely diced carrots can add incredible flavor and nutrients.
- You can also layer in thin slices of grilled eggplant or zucchini for more “noodle-like” texture.
- Sauce Hacks:
- In a pinch, if you don’t have pre-made tomato sauce, combine a can of crushed tomatoes with a good amount of Italian seasoning, a pinch of sugar (or a low-carb sweetener), and some salt and pepper for a quick, flavorful alternative.
- Presentation & Portions:
- Instead of a large casserole, try making individual “lasagna boats.” Simply layer your cheese, tomato sauce, and sausage mixture inside each cooked spaghetti squash half. This is a fun and easy way to serve individual portions.
Recipe FAQs for Spaghetti Squash Lasagna
Absolutely! This recipe is fantastic for meal prep, and you have several convenient options. You can assemble the entire lasagna ahead of time, but hold off on baking it. Simply cover the baking dish tightly with foil or plastic wrap and refrigerate for up to 24 hours. When you’re ready to enjoy, bake it as directed, adding a few extra minutes to account for the chill. Alternatively, you can ingredient prep by preparing the tomato sauce, cooking the spaghetti squash, and cooking the meat/veggie mixture up to three days in advance. This way, all you have to do is quickly assemble and bake the lasagna on the day you plan to serve it, significantly cutting down on active cooking time.
Yes, spaghetti squash is indeed considered a low-carb vegetable, especially when compared to other winter squash varieties. Unlike many starchy vegetables, spaghetti squash offers a much lower carbohydrate count, making it an excellent pasta alternative for those watching their carb intake. In a typical one-cup serving of cooked spaghetti squash, you’ll find approximately 10 grams of total carbohydrates. For more detailed nutritional information and benefits of spaghetti squash, you can refer to authoritative sources like this USDA FoodData Central post.
Yes, spaghetti squash freezes exceptionally well, both on its own and when incorporated into a dish like this lasagna! If you’re planning to freeze this spaghetti squash lasagna, it’s beneficial to remove as much liquid as possible from the cooked squash strands before assembly and baking. This extra step helps maintain a better texture after thawing and reheating. Once fully cooked and cooled, wrap individual portions or the entire dish tightly to prevent freezer burn. For more detailed guidance on freezing and storage, please check the “Meal Prep and Storage” section below.
This spaghetti squash lasagna is a wonderfully hearty and substantial meal on its own, with each portion being quite filling. Given its richness, I personally prefer to enjoy it with a simple, light side salad dressed with a vinaigrette to provide a refreshing contrast. For families, especially those with kids who might enjoy a more traditional pairing, a side of homemade garlic toast or crusty bread is always a popular choice. A side of steamed green beans or broccoli would also complement the flavors beautifully.
Meal Prep and Storage Tips for Your Lasagna
This Spaghetti Squash Lasagna is not only delicious but also incredibly convenient for meal prepping, making your healthy eating journey even easier. Proper storage and reheating ensure you can enjoy this dish days or even months after preparation.
To Prep Ahead:
- Assemble and Refrigerate: This lasagna is an ideal candidate for assembling in advance. You can prepare the entire dish, layer by layer, up to 24 hours before you plan to bake it. Simply follow all the recipe instructions up to the point of baking, then cover your baking dish tightly with aluminum foil or plastic wrap. Refrigerate it until you’re ready. When it’s time to eat, just pop it into the oven and bake as directed, potentially adding an extra 5-10 minutes to the baking time since it will be chilled.
- Ingredient Prep: Another excellent option is to prepare individual components in advance. Cook your spaghetti squash, make your homemade tomato sauce, and cook the meat/veggie mixture up to three days ahead of time. Store each component separately in airtight containers in the refrigerator. On the day you want lasagna, all that’s left to do is quickly assemble the layers and bake! This significantly reduces active cooking time on busy evenings.
To Store Leftovers:
- If you find yourself with leftovers or have baked the entire lasagna and want to save some for later, allow the dish to cool completely to room temperature first. This prevents condensation from forming and keeps the lasagna fresh. Once cool, transfer any remaining lasagna to an airtight container. Store it in the refrigerator for up to 3-4 days.
To Freeze for Later:
- Spaghetti Squash Lasagna freezes wonderfully, making it perfect for stocking your freezer with healthy, ready-made meals. To freeze, you have a couple of options:
- Individual Portions: For easy grab-and-go meals, cut the cooled lasagna into individual servings. Wrap each portion tightly in plastic wrap, then an additional layer of aluminum foil to prevent freezer burn.
- Entire Dish: If freezing the whole dish, ensure it’s completely cooled. Cover the baking dish tightly with multiple layers of plastic wrap and then aluminum foil.
Place the wrapped lasagna portions or the entire dish in an airtight freezer-safe container or a large resealable freezer bag. Frozen lasagna can be safely stored for 2-3 months. Label with the date to keep track!
To Reheat:
- From Refrigerator (Baked): Reheat individual portions or the entire dish in a preheated oven at 350°F (175°C) until thoroughly heated through and bubbly. This typically takes about 15-20 minutes for individual servings or 30-40 minutes for a larger dish, depending on its size. Covering with foil for the first part of reheating can help prevent the top from drying out.
- From Refrigerator (Microwave): For a quicker option, individual servings can be reheated on a microwave-safe plate for 2-4 minutes, or until hot. Stirring halfway through can help with even heating.
- From Freezer: For best results, it is highly recommended to thaw frozen lasagna in the refrigerator overnight before reheating. Once thawed, follow the reheating instructions for refrigerated lasagna above. If reheating from frozen, it will take considerably longer in the oven (possibly 45-60 minutes or more, covered with foil).
Discover More Healthy Spaghetti Squash Recipes
If this Low Carb Spaghetti Squash Lasagna has turned you into a spaghetti squash enthusiast, you’re in for a treat! This versatile vegetable can be transformed into countless delicious and healthy dishes. Explore these other fantastic recipes that utilize spaghetti squash as a perfect low-carb base:
Mediterranean Stuffed Spaghetti Squash Boats
Shrimp Scampi with Spaghetti Squash
Simple Spaghetti Squash with Meat Sauce
Spaghetti Squash Chicken Alfredo | What Molly Made
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Spaghetti Squash Lasagna Casserole
Pin Recipe
Ingredients
- Olive oil cooking spray [I use my EVO]
- 1 lb spicy Italian turkey sausage casings removed
- 1/4 onion diced
- 2 cloves garlic minced
- 1 1/4 cup ricotta cheese WW can use fat free
- 1 egg
- 1 1/2 cups homemade tomato sauce or a no sugar added jarred sauce like Rao’s
- 1 cooked spaghetti squash about 4 cups of squash
- 2/3 cup mozzarella cheese
- 1 tablespoon parmesan cheese
- Fresh basil
- Salt and pepper
Instructions
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Spray a large skillet or cast-iron pan with olive oil cooking spray. Heat over medium heat, then add the diced onion and sauté until soft and translucent. Add the Italian turkey (or chicken) sausage, breaking it up with a spoon, and brown until cooked through. Finally, stir in the minced garlic and cook for an additional minute until fragrant. Remove from heat.
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Once your spaghetti squash is cooked and cooled, discard the seeds and use a fork to scrape out the “spaghetti” strands. To remove excess moisture, place the cooked squash in a clean kitchen towel or paper towels and give it a firm squeeze over a sink or bowl. Season the dried squash with a little salt and pepper.
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In a medium bowl, combine the ricotta cheese with one egg, the Parmesan cheese, and a sprinkle of black pepper. Stir until well mixed.
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Preheat your oven to 350°F (175°C). Lightly spray a casserole dish (approx. 9×13 inch) with olive oil cooking spray to prepare for layering.
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Spoon about half of your homemade or jarred tomato sauce evenly across the bottom of the casserole dish, creating a flavorful base.
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Next, spread the cooked sausage and onion mixture evenly over the sauce. Layer the seasoned spaghetti squash strands over the sausage. Then, add the remaining tomato sauce over the squash, spreading it gently. Sprinkle some fresh chopped basil over this layer.
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Finally, dollop the ricotta cheese mixture over the sauce. Gently spread it out, then evenly sprinkle the shredded mozzarella cheese over the top.
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Bake in the preheated oven for 15-20 minutes, or until the cheese is melty and bubbly. For a golden-brown top, you can carefully broil on low for 5-10 minutes at the very end, but watch carefully as it can brown quickly.
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Remove the lasagna from the oven and let it sit for a few minutes before serving. If there’s any excess water at the bottom of your pan, you can carefully drain it from a corner or serve with a slotted spoon.
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Garnish generously with fresh basil leaves just before serving and enjoy your delicious low-carb lasagna!
Notes
WW: 9 points (per serving) [Calculated using hot italian turkey sausage, part skim mozzarella cheese, and fat free ricotta cheese]
To Prep Ahead:
- This Spaghetti Squash Lasagna is an excellent candidate for meal prep. You can assemble it up to 24 hours before baking. Just follow the recipe instructions up to the point of baking, then cover the baking dish with foil and refrigerate. When you’re ready to enjoy it, simply bake as directed (you may need to add 5-10 minutes to baking time for a chilled dish).
- Another option is to prep the tomato sauce, squash, and meat/veggie mixture up to three days in advance. Then all you have to do is assemble and bake the lasagna the day you want to eat it.
To Store:
- If you have leftovers or want to store a fully cooked lasagna, allow it to cool completely to room temperature. Store any remaining lasagna in an airtight container in the refrigerator for up to 3-4 days.
To Freeze:
- To freeze Spaghetti Squash Lasagna, wrap individual portions or the entire cooled dish tightly with plastic wrap or aluminum foil. Place the wrapped lasagna in an airtight container or a resealable freezer bag to prevent freezer burn. Frozen lasagna can be stored for 2-3 months.
To Reheat:
- Reheat in a preheated oven at 350°F (175°C) until the lasagna is heated through, typically about 15-20 minutes for individual portions or 30-40 minutes for the entire dish. Covering with foil helps prevent drying.
- Alternatively, you can microwave individual servings on a microwave-safe plate for 2-4 minutes or until hot.
- To reheat frozen lasagna, it’s best to thaw it in the refrigerator overnight and then follow the oven reheating instructions above.