Cake with Strawberry Filling Recipe

This layer cake hides a glossy, cooked-from-scratch strawberry filling between fluffy buttercream and soft sponge. Slice in and you get ribbons of jammy, bright strawberry running through every layer, the kind of bakery look that's far simpler to pull off than it appears.

Why you'll love this

• A real cooked strawberry filling thickened to a glossy, sliceable jam, not a runny puree
• Frozen strawberries mean you can make it any time of year, no need to wait for peak season
• Three layers stacked with buttercream and crowned with fresh berries for a showstopper finish
• Works with homemade sponge or store-bought layers, so you control how much you bake

Key ingredients & swaps

• Frozen strawberries — cooked down into the filling for deep, concentrated berry flavour; no need to thaw first, just simmer them straight from frozen until they break down and release their juice
• Cornstarch — the thickener that turns watery berries into a glossy, holdable jam; always whisk it smooth with the water first so you don't get lumps or a runny filling
• Lemon juice — brightens and balances the sweetness so the filling tastes fresh rather than flat; a tablespoon is enough to sharpen the berries
• Buttercream frosting — frosts the outside and, just as importantly, gets piped as a dam ring on each layer to keep the filling from squeezing out the sides
• Sponge or vanilla cake layers — the soft, neutral canvas that lets the strawberry shine; bake your own or use store-bought, but make sure they're fully cooled before stacking
• Fresh strawberries — sliced over the top for decoration and a fresh, juicy contrast to the cooked filling inside

How to make it (step by step)

1. 1

   Start the slurry

   In a medium saucepan, whisk the water and cornstarch together until completely smooth before any heat goes on. Getting it lump-free now is what guarantees a glossy filling instead of a grainy, runny one.

2. 2

   Cook the filling

   Add the frozen strawberries, sugar and lemon juice and cook over medium heat, stirring frequently, for 10 to 15 minutes. The berries will collapse and the mixture will bubble, darken and thicken to a jam-like consistency that coats the back of the spoon.

3. 3

   Cool it completely

   Take the filling off the heat and let it cool all the way to room temperature, then chill if you can. It firms up considerably as it cools, and warm filling will melt the buttercream and slide right out of the cake.

4. 4

   Dam and fill the first layer

   Set the first cooled cake layer on your plate, spread a layer of buttercream, then pipe a ring of buttercream around the rim and spoon half the cooled filling inside the dam so it can't escape the edges.

5. 5

   Stack and repeat

   Add the second layer and repeat: buttercream, a dam ring, and the rest of the strawberry filling inside it. Keep the layers level as you go so the finished cake doesn't lean.

6. 6

   Frost and chill

   Top with the third layer, frost the outside and top with the remaining buttercream, then decorate with sliced fresh strawberries. Refrigerate at least 1 hour so everything sets before you slice clean wedges.