Wherever the Vanilla Custard Slice originated, it’s definitely a bakery classic in Australia. A thick but soft layer of custard between sheets of puff pastry, all topped off with a sweet vanilla (or sometimes passionfruit) icing.

Love easy lemon desserts? Then you love this lemon curd mousse or these lemon curd cookies.

A batch of vanilla custard slice on a sheet of baking paper on a wooden board. Once sits on a plate in front with a bite taken out

Along with Florentines, meringues and lamingtons, no Aussie bakery would be complete without this soft, creamy pastry dessert.

To be honest, I didn’t realise how delicious these bakery treats were until adulthood. As a kid, the only reason a bakery existed was for meringues. Crispy, sweet, colourful, dotted with sprinkles, meringues! Once I did discover the good old vanilla slice, I realised I’d been missing something pretty special.

I couldn’t resist the temptation to add a little zing of lemon to my recipe but you can just as easily leave it out.

2 pieces of vanilla slice - one with white icing and the other with passionfruit icing on a sheet of baking paper with lemon slices sitting next to them.

Birdseye view of a bowl filled with vanilla pastry creamWhat Is Vanilla Slice?

Similar to mille-feuille but with less pastry, the traditional vanilla slice has a thick, sweet custard set between two layers of puff pastry. It’s most often topped with a white vanilla icing but sometimes it’s pink and others, it is a passionfruit icing. I’ve also seen it topped just with a good dose of icing (powdered) sugar but the icing is the way to go in my opinion.

With 3 layers of goodness, this recipe is actually a pretty simple one and one that is very easy to make at home.

How to make it

  1. You’ll start by baking 2 sheets of pre-rolled puff pastry in the oven until golden.
  2. The pastry is cut to size to fit into a 8×8 inch square baking tin. This is a simple matter of placing the tin on top of the baked pastry (once it has cooled) and using a sharp knife to cut through it.
  3. The custard made totally from scratch is a mixture of milk, cream, sugar, butter and vanilla that is heated just until the first bubbles start to appear.
  4. This gets slowly drizzled into a mixture of egg yolks, water and corn flour whilst continuously beating.
  5. It all gets added back to the saucepan and whisked slowly over low-medium heat until it’s nice and thick. The custard will look almost bouncy when it’s ready and it will dollop off the whisk and not merge straight into itself again.
  6. Layer it up – line the square baking tin with baking paper and place one piece of the baked puff pastry in the bottom. Whisk the lemon juice and zest into the custard then pour it over and level it out. Add the top layer of pastry.
  7. After letting it set for a good 4 hours (or overnight is even better), just make a simple 2 ingredient icing and pour it over the top.

Tips For The Best Vanilla Slice

  • Keep the puff pastry flat while baking: To keep the puff pastry from puffing up too much, sit a baking tray on top of them as they bake. This will result in flatter but still super flaky puff.
  • To cut the cooked puff pastry: A large chefs knife pressed directly down is the way to go. Don’t use a sawing motion or you’ll just be left with a flaky pastry mess.
  • Use a heavy based saucepan: I use them for everything but especially when making delicate desserts and candies, a heavy based saucepan is a lifesaver. It distributes the heat more slowly and evenly so they don’t burn or split.
  • Make sure to temper the eggs: Tempering eggs means to slowly bring their temperature up to match the cooked component so they stay smooth and liquid rather than scrambling. It’s easy don’t worry – just make sure to slowly drizzle the hot liquid into them whilst constantly beating / mixing.
  • Pre-cut the top layer of pastry: I like to pre-cut my top pastry layer into the sizes I will cut the slices once it’s set. It’s much easier to cut slices this way. If you don’t pre-cut it, I find the custard layer can be squished as you’re trying to cut it later.
  • Go easy with liquid in the icing: In my icing, I use lemon juice to complement the lemon flavour in the custard but you can use just water or milk. Add a little at a time as it can become too runny very easily. It needs to be quite thick so that it takes at least 10 seconds to settle into itself again when you lift the spoon out.

A closeup of a piece of vanilla custard slice with more in the background. It sits on a wooden board

Variations

  • Leave out the lemon: If you’re a purist and / or want that traditional vanilla slice, simply leave out the lemon components and add an extra teaspoon of vanilla to the custard mix. That’s it.
  • Passionfruit icing: Passionfruit icing is absolutely lovely and works well with the both the vanilla and lemon varieties of this slice. Substitute the lemon juice in the icing for passionfruit pulp. You may need a little extra but add it a little at a time so that it’s not too runny like mine was in these pics. Still indulgent and delicious though. Passionfruit pulp is often sold in the freezer section or tinned fruit section if you can’t find fresh.
  • Chocolate: You could use this recipe for my Tim Tam Chocolate Custard Slice for the custard portion and use the puff pastry as mentioned in this one. Dust it with cocoa or top it with a chocolate icing instead (icing sugar, cocoa and milk or water)
  • No icing: simply dust the top with icing sugar at the time of serving if you prefer
  • Lattice biscuits: You can swap the puff pastry with lattice biscuits. This will be even easier to make but not as easy to eat.

Can Custard Slice Be Frozen

No. Custard doesn’t freeze well so this is a treat to eat straight from the fridge.

Speaking of which, store the Lemon Vanilla Custard Slice in an airtight container in the fridge for 3-4 days.

A batch of vanilla custard slice on a sheet of baking paper on a wooden board. One is topped with passionfruit icing

This delightful bakery treat is so easy to make at home. Rich, creamy and delicious Lemon Vanilla Custard Slice is wonderful for afternoon tea or to take when visiting friends.

More Amazing Lemon Recipes

A batch of vanilla custard slice on a sheet of baking paper on a wooden board. Once sits on a plate in front with a bite taken out

Lemon Vanilla Custard Slice

Yield: 12 serves
Prep Time: 7 minutes
Cook Time: 8 minutes
0 minutes
Total Time: 2 hours 15 minutes
4.9 from 10 ratings
This classic Australian bakery treat, the Vanilla Custard Slice is a sweet, creamy set-custard between with puff pastry, topped with icing. This recipe has an irresistible tang of lemon and is easy to make at home.
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Ingredients

  • 2 sheets puff pastry
  • 1 ½ cups milk
  • 1 1/2 cups thickened (heavy) cream
  • 57 g (1/4 cup) unsalted butter
  • 1 teaspoon vanilla extract
  • 1/2 cup white granulated sugar
  • 1/2 cup cornflour / cornstarch (spooned & levelled)
  • ¼ cup water
  • 1 teaspoon lemon zest
  • 1 ½ tablespoons lemon juice (notes)
  • 4 egg yolks (from large eggs)

FOR THE ICING

  • 1 1/2 cups icing (powdered) sugar
  • 2 tablespoons lemon juice (notes)

For best results, always weigh ingredients where a weight is provided

Instructions
 

  • Preheat oven to 200C / 395F / 180C.
  • Line two baking trays and place a sheet of puff pastry on each one. Lay another piece of baking paper on top of each, then place another baking tray on top of each without pressing down.
  • Bake for 20-25 minutes or until golden then transfer to a wire rack to cool.
  • Heat together the milk, cream, butter, vanilla. and sugar a heavy based saucepan over low to medium heat until bubbles just start to appear. Make sure to stir regularly. Turn the heat off.
  • Place the cornflour, water, lemon zest, lemon juice and egg yolks in a large bowl and beat with a handheld beater just until combined and lightened.
  • With the beater on low, slowly drizzle the hot milk mixture into the egg mixture. Don't rush it or you may end up scrambling your eggs.
  • Return it all to the saucepan and heat over low-medium heat, whisking constantly, until it thickens. It will get quite thick after 4-5 minutes. It is ready when it starts looking 'bouncy' almost and when dolloping custard on top of itself, it takes a while to settle back into itself. Turn the heat off.
  • Sit an 8x8 inch square baking tin on top of one of the pieces of baked puff pastry. Use a large, sharp knife to cut straight down through the pastry around the base of the pan so you have a square that will fit inside the pan.
  • Repeat with the second sheet of puff then slice this second square into 8, 9 or 12 pieces (whichever size you want to serve).
  • Line the square tin with baking paper, then place the first puff square in the bottom.
  • Pour the custard over the top and level it out with an offset spatula.
  • Place the sliced pieces of the second sheet of puff over the top, butting up to each other.
  • Place in the fridge to set for at least 4 hours (or overnight)
  • At any time, once the custard is cool, you can make the icing.
  • Mix the icing sugar and lemon juice until it forms a smooth paste. Pour then level it over the top of the custard slice, still in the tin. This should set at least 1 hour before serving.

Notes

Equipment used: Handheld beater, 8x8 inch sqare baking tin, whisk and silicone spatula
  1. I use a standard Australian 20ml tablespoon (= 4 teaspoons worldwide)
  2. For best results, you should always weigh ingredients like flour and sugar. Kitchen scales are relatively cheap but if you can’t weigh the ingredients, use the spoon and level method (don’t scoop).

Variations:

  • Leave out the lemon: For a raditional vanilla slice, simply leave out the lemon components and add an extra teaspoon of vanilla to the custard mix. That’s it.
  • Passionfruit icing: Substitute the lemon juice in the icing for passionfruit pulp. You may need a little extra but add it a little at a time so that it’s not too runny.
  • Chocolate: You could use this recipe for my Tim Tam Chocolate Custard Slice for the custard portion and use the puff pastry as mentioned in this one. Dust it with cocoa or top it with a chocolate icing instead (icing sugar, cocoa and milk or water)
Want more bars and slices? Click here
Calories: 378kcal
Author: Marie Roffey
Course: Afternoon Tea, Dessert, Snack, Sweets
Cuisine: Australian, British
Have you tried this recipe?Don't forget to leave a rating and comment below and let me know how it was! I love hearing from you. Nutrition information is approximate and derived from an online calculator. The brands you use may cause variations.

A batch of vanilla custard slice on a sheet of baking paper on a wooden board.