Vanilla Slice is a timeless bakery favorite made with layers of crisp puff pastry and a thick, silky vanilla custard that slices beautifully once chilled. Rich yet balanced, this dessert delivers that perfect contrast between flaky pastry and creamy filling in every bite. Itโs elegant enough for entertaining but simple enough to prepare at home with pantry staples.
This version sets firm without gelatin, relying on egg yolks and cornstarch for a smooth, luxurious texture that holds its shape. Finished with a dusting of powdered sugar, itโs a classic treat that never goes out of style.
Yield & Timing
- Yield: 9 large squares or 16 small slices
- Prep time: 25 minutes
- Cook time: 40 minutes
- Chill time: 4 hours (or overnight)
Ingredients
Pastry
- 2 sheets puff pastry, thawed
Custard Filling
- โ cup (133 g) granulated sugar
- ยฝ cup (60 g) cornstarch
- ยผ teaspoon kosher salt
- 6 large egg yolks
- 3ยฝ cups whole milk
- Seeds from 1 vanilla bean (or 2 teaspoons vanilla extract)
- 4 tablespoons (60 g) cold unsalted butter, cubed
For Serving
- Powdered sugar, for dusting
How to Make Vanilla Slice
1. Bake the Puff Pastry
Preheat oven according to puff pastry package instructions. Place pastry sheets on baking trays lined with parchment paper. Bake for 35โ45 minutes, or until deeply golden and crisp, checking around the 30-minute mark. Allow pastry to cool completely.
2. Trim the Pastry
Using a serrated knife, carefully trim both pastry sheets to fit an 8ร8-inch square pan. Avoid pressing down to keep the layers flaky.
3. Mix the Custard Base
In a medium saucepan, whisk together sugar, cornstarch, and salt. Add egg yolks and whisk until smooth and fully combined.
4. Heat the Milk
In a separate saucepan, warm the milk over medium heat until steaming. Do not let it boil.
5. Temper the Eggs
Slowly whisk 1 cup of warm milk into the egg mixture to temper. Gradually pour the tempered mixture back into the saucepan with the remaining milk, whisking constantly.
6. Cook the Custard
Cook over medium heat, whisking continuously, until thickened and bubbling, about 5โ7 minutes. Remove from heat and whisk in vanilla and cold butter until smooth and glossy.
7. Assemble
Line an 8ร8 pan with foil, leaving overhang on all sides. Place one pastry sheet on the bottom. Pour warm custard over the pastry and smooth evenly. Top with the second pastry sheet and gently press to adhere.
8. Chill
Cover tightly and refrigerate for at least 4 hours or overnight until fully set.
9. Slice & Serve
Lift out using foil overhang. Slice with a serrated knife, wiping between cuts for clean edges. Dust generously with powdered sugar before serving.
Notes & Tips
- Make-Ahead: Can be prepared up to 24 hours in advance
- Storage: Refrigerate in an airtight container for up to 3 days
- Freezing: Not ideal, but possible for up to 1 month (texture may soften)
- Clean Cuts: Score the top pastry before slicing fully through
Why This Recipe Works
This vanilla slice balances structure and creaminess perfectly. The custard sets firm without becoming rubbery, while the puff pastry stays crisp for that classic bakery texture. Itโs simple, refined, and endlessly satisfying โ the kind of dessert that feels nostalgic and impressive all at once.

