1Preheat oven to 180°C/160° fan assisted/gas 4. Line the bottom of two 20cm (8inch) springform cake tins with parchment paper. Grease the sides of the tins with butter then dust with flour.
2For the sponge, beat the butter, sugar and lemon zest together with an electric mixer until well creamed.
3Add the eggs 2 at a time, adding the vanilla and lemon juice with the last 2 eggs. Beat for about 2-3 minutes with each addition, making sure to scrape down the sides of the bowl between each addition.
4Add the flour and beat just until there is no dry flour visible in the batter.
5Divide batter equally between the prepared baking tins then smoothen the top with a spatula. Bake until a toothpick inserted in the centre of the cakes come out clean, about 35-40 minutes.
6Remove from oven and leave to cool in baking tins on a wire rack for about 10 minutes, then turn sponges out of tins and leave to cool completely.
7For the coulis, puree strawberries then cook on medium heat in a saucepan until reduced by half. Stir often.
8Set aside to cool completely.
9For the buttercream, beat butter until smooth. Add the rest of the ingredients and beat slowly to start until ingredients are incorporated, then increase speed and beat until frosting is smooth and creamy. Scrape down the sides of the bowl as you go.
10To assemble, set aside 8 strawberries for decorating, then cut the remaining into thick slices.
11Place a cooled sponge on a serving plate then spread about ½ a cup of buttercream over the top but not right to the edge of the sponge. Arrange sliced strawberry slices on the buttercream, pressing them in lightly.
12Place the second sponge on top then use the rest of the buttercream to cover the cake.
13Finally, use a large star piping nozzle to pipe 8 rosettes on top of the cake. Press a reserved whole strawberry into each rosette and finish off with a piece of lemon.
For the sponge
For the strawberry coulis
For the buttercream frosting