The Ultimate Vegan Vanilla Slice Recipe: Flaky Pastry & Creamy Custard Perfection

Indulge in a beloved bakery classic reinvented with this incredible Vegan Vanilla Slice recipe. Imagine perfectly smooth, rich, and creamy vanilla custard nestled between two layers of exquisitely flaky, golden puff pastry. Each bite is then elevated by a vibrant, sweet, and tangy passion fruit glaze, adding an irresistible zest that beautifully complements the creamy filling. This delightful treat, often called a vegan custard slice, delivers all the nostalgic charm and deliciousness of the traditional version, but without any eggs or dairy, making it accessible for everyone to enjoy. It’s surprisingly easy to prepare at home, allowing you to recreate this iconic dessert that’s just as good, if not better, than your favorite non-vegan bakery find.

What Are Vanilla Slices?: A Beloved Bakery Staple

Vanilla slice, affectionately known as custard slices or even ‘snot blocks’ in some parts of Australia due to their distinctive texture and appearance, are a hugely popular and classic bakery treat. They hold a special place in the hearts of dessert lovers across the UK, Australia, and New Zealand. At their core, these delightful squares feature a generous, thick layer of set, vanilla-flavored custard, perfectly sandwiched between two sheets of light, crisp, and incredibly flaky puff pastry. The top is typically finished with either a simple dusting of icing sugar or, as in this recipe, a sweet and sometimes tangy glaze. While they bear a resemblance to the elegant French mille-feuille (or Napoleon), vanilla slices are generally less intricate, opting for fewer, thicker layers for a more robust, satisfying bite.

Historically, these treats have been a cornerstone of local bakeries, often enjoyed with a cup of tea or coffee. The contrast between the delicate crunch of the pastry and the smooth, cool, and rich custard is what makes them so irresistible. Creating a vegan version means everyone can experience this iconic dessert without compromising on flavor or texture. This recipe ensures that the custard is wonderfully creamy and perfectly set, while the puff pastry remains beautifully crisp, replicating the authentic experience to perfection.

Ingredient Details: Crafting the Perfect Vegan Custard Slice

Achieving a truly exceptional vegan vanilla slice hinges on selecting the right ingredients. Each component plays a vital role in creating the iconic flavor and texture profile that makes this dessert so beloved. Here’s a closer look at what you’ll need and why:

Custard powder: This is the secret to a perfectly set, creamy, and flavorful custard. Custard powder typically contains cornstarch (or similar thickening agents), sugar, and vanilla flavoring, often with a hint of natural coloring to give it that classic yellow hue. Most brands, such as Bird’s, are naturally vegan-friendly, but always double-check the label for peace of mind. While cornstarch can be used as a substitute in a pinch, I highly recommend sticking with custard powder. It not only provides the necessary thickening power but also contributes to the distinctive taste and vibrant color that makes vanilla slices so appealing.

Vegan butter: Incorporating a good quality vegan block butter into the custard filling is crucial for achieving that luxurious richness and velvety texture. It also aids in helping the custard to set firmly, which is essential for neat slicing. While spreadable vegan butter can be used if that’s all you have, it contains more water and less fat, which can result in a softer set custard. If using spreadable butter, I recommend increasing the custard powder to 110g to compensate for the higher moisture content and ensure your custard is firm enough to hold its shape.

Milk: For the most authentic and delicious custard, I highly recommend using unsweetened soya milk. It offers a creamy consistency and a neutral flavor that allows the vanilla to truly shine. Other plant-based milks can certainly be used, but be aware that their distinct flavors (e.g., oat, almond, coconut) might subtly alter the overall taste of the custard. Additionally, some alternative milks may not yield the same rich creaminess as soya milk, potentially resulting in a slightly less decadent custard.

Vanilla: Vanilla is, of course, the star of the show! For intense, fragrant vanilla notes, I prefer using vanilla bean paste, which combines the convenience of extract with the visual appeal and potent flavor of real vanilla bean seeds. You can also use the seeds scraped directly from a fresh vanilla pod for an exquisite flavor. If these are unavailable, a good quality vanilla extract will still work wonderfully, though you might need a touch more to achieve the desired intensity.

Sugar: You’ll need two types of sugar for this recipe. Caster sugar (or granulated sugar) is perfect for the custard, dissolving easily and providing balanced sweetness. Icing sugar (also known as powdered sugar or confectioners’ sugar) is essential for both dusting the puff pastry before baking (which helps with crispiness) and for preparing the silky-smooth glaze. I strongly advise against swapping these for other types of sugar or alternative sweeteners, as they may impact the texture and consistency of both the custard and the glaze.

Puff pastry: The flaky layers of puff pastry are integral to the vanilla slice experience. The good news is that most store-bought puff pastry, especially ready-rolled sheets, are accidentally vegan-friendly. However, always double-check the ingredient list to ensure it’s not “all-butter” pastry, which contains dairy. Using ready-rolled pastry is a fantastic time-saver and ensures uniform thickness, making the entire process much more convenient and straightforward.

Passion fruit: While optional, a simple passion fruit glaze adds a fantastic dimension to these vegan vanilla slices. Its bright, tangy, fruity, and slightly citrusy flavor provides a wonderful contrast to the rich, creamy vanilla custard, creating a truly memorable dessert. If passion fruit isn’t your preference or is unavailable, you can simply dust the slices with a little icing sugar before serving for a classic finish, or opt for a plain vanilla glaze.

How To Make Vegan Vanilla Slice: A Step-by-Step Guide

Creating these delightful vegan vanilla slices might seem intricate, but with a little patience and attention to detail, you’ll be rewarded with a bakery-quality treat right in your own kitchen. The process involves preparing the pastry, making the creamy custard, assembling the layers, and finally, adding the delicious glaze. Follow these steps for perfect results:

Before you begin, ensure your oven is preheated to 200℃/180℃ fan/400℉/gas mark 6. Proper preheating is key to getting that beautifully puffed and crisp pastry.

Step 1: Preparing the Pastry Base. Carefully unroll one sheet of ready-rolled puff pastry and lay it flat on a baking tray, making sure to keep the baking paper it came with underneath. This prevents sticking. Lightly dust the pastry with a fine layer of icing sugar using a small sieve – this helps achieve extra crispiness and a lovely caramelization. Cover this pastry sheet with another piece of baking paper, then place a second baking tray directly on top. To weigh it down and prevent excessive rising, place two loaf tins filled with baking beans (or dried rice) on the top tray. This crucial step ensures your pastry bakes flat and evenly crisp, perfect for the base of your vanilla slice.

Step 2: Baking the Pastry. Bake the weighted-down pastry in the preheated oven for approximately 30-35 minutes, or until it turns a beautiful golden brown and is wonderfully crisp. Once baked, carefully remove the top baking tray and the weights. Slide the cooked pastry sheet onto a wire cooling rack to allow it to cool completely. Repeat this exact process with the second sheet of puff pastry, ensuring you have two perfectly baked, flat, and flaky pastry layers.

Step 3: Sizing the Pastry. Once both pastry sheets are cool, it’s time to cut them to size. Use the base of a 23cm (9-inch) square cake tin as a guide. With a very sharp knife, carefully trim each baked pastry sheet into a precise 23cm square. Line your chosen cake tin with two strips of baking paper, leaving some overhang on each side. This smart trick will allow you to easily lift the entire slice out of the tin later. Place one of your perfectly cut pastry squares into the base of the lined tin.

Step 4: Pre-cutting the Top Pastry. Take the second pastry square and cut it into 10 evenly sized rectangles. Achieve this by first slicing it in half horizontally, then dividing each half into five vertical strips. This crucial step of pre-cutting the top layer of pastry makes serving the vanilla slices significantly easier later, preventing any squishing of the delicate custard when slicing through the finished dessert. Set these pre-cut pastry pieces aside.

Step 5: Making the Vegan Custard. In a large saucepan, combine the custard powder and sugar. Gradually whisk in the plant-based milk, adding only a small amount at a time at first to create a smooth paste, then slowly incorporating the rest to prevent any lumps. Stir in the vanilla paste (or extract/seeds). Place the saucepan over a medium heat and, stirring continuously with a balloon whisk, bring the mixture to a boil. It will thicken considerably as it cooks. Once thick and bubbling, remove the pan from the heat, add the vegan block butter, and stir vigorously until the butter has completely melted and is fully incorporated into the smooth, luscious custard.

Step 6: Assembling the Base Layer. Immediately pour the hot, freshly made custard over the pastry base that you placed in the lined cake tin. Work quickly and spread the custard evenly across the pastry using an offset spatula or the back of a spoon, ensuring a smooth, level layer. Speed is important here, as the custard will begin to set as it cools.

Step 7: Adding the Top Pastry and Chilling. While the custard is still warm and pliable, carefully arrange the pre-cut pastry rectangles on top of the custard layer. Press them down very gently to ensure they adhere to the custard. This helps to secure the top layer once set. Transfer the entire tin to the refrigerator and chill for at least 4 hours, or preferably overnight, to allow the custard to set completely and firm up perfectly.

Step 8: Glazing and Serving. Once the vanilla slice is thoroughly chilled and set, it’s time for the final touches. Use the overhanging parchment paper to carefully lift the entire slab out of the tin. Place it on a cutting board. Using a very sharp knife, slice the large block into individual portions, following the pre-cut lines of the top pastry layer. For the passion fruit glaze, simply sift icing sugar into a bowl, stir in melted vegan butter, and then add the pulp from fresh passion fruits. Mix until smooth. Spoon a small amount of the glaze onto the center of each slice and gently spread it out with the back of a teaspoon. Alternatively, a simple dusting of icing sugar or a plain vanilla glaze works beautifully. Serve immediately and enjoy your homemade vegan vanilla slices!

Top Tips for Perfect Vegan Vanilla Slices

Achieving bakery-perfect vegan vanilla slices is easier than you think with a few key tricks. These tips will help you navigate the process and ensure your dessert turns out flawless every time:

• **Weighting Down the Pastry:** This might seem like an extra step, but weighing the puff pastry down while it bakes is absolutely crucial. It prevents the pastry from puffing up too much, ensuring a wonderfully flat, crisp, and even base and top for your slices. This controlled rise also helps achieve that delicate, flaky texture rather than an overly airy one.
• **Pre-Cut Top Pastry is Key:** Do not skip the step of cutting the top sheet of pastry into individual portions *before* you assemble the slices. This is a game-changer! Trying to cut through the crisp pastry and set custard later can be messy and often results in squishing the creamy filling. Pre-cutting ensures clean, neat slices with minimal fuss when you’re ready to serve.
• **Enjoy Freshness for Optimal Texture:** While these vegan vanilla slices are utterly delicious, they are truly at their best when eaten as fresh as possible, ideally within a few hours of the custard fully setting. Over time, the moisture from the custard will inevitably begin to soften the crisp puff pastry. They will keep well in an airtight container in the fridge for around 3 days, but for the ultimate experience, serve them soon after they’ve chilled.
• **Customizing Custard Firmness:** This recipe calls for a custard that sets to a firm consistency, which makes the bars easy to slice neatly and handle without falling apart. Despite its firmness, it remains wonderfully silky and melt-in-your-mouth. If you prefer a slightly softer, more yielding custard, you can reduce the amount of custard powder to 70g. Experiment to find your perfect texture!
• **Glaze Alternatives and Options:** The passion fruit glaze adds a fantastic tangy counterpoint, but it’s entirely optional. For a simpler approach, a mere dusting of icing sugar is elegantly classic. You can also create a basic pourable glaze by mixing icing sugar with a tiny amount of plant milk, water, or even a squeeze of lemon juice (for an extra citrusy kick) until it reaches your desired consistency.
• **Glaze After Cutting:** For the neatest finish, I find it’s best to apply the glaze *after* you’ve sliced the vanilla slab into individual portions. This allows you to spoon a controlled amount of icing onto each bar and spread it evenly with the back of a teaspoon, preventing glaze from running down the sides or creating an uneven appearance.

More Vegan Dessert Bars Recipes:

• Vegan lemon bars
• Jaffa cake bars
• Vegan lemon Bakewell slices
• Berry crumble bars
• Fudgy vegan brownies
• Chocolate raspberry crumble bars

If you tried this recipe let me know how it went! Rate it, leave a comment or tag @domestic_gothess on Instagram and hashtag it #domesticgothess

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