Bloom 6.5 gelatine sheets in cold water for 5 to 10 minutes. Drain the softened gelatine sheets before using.

Crush 160 g butter biscuits into fine crumbs. Combine the crumbs with 35 g melted unsalted butter and 1 tsp vanilla essence.

Press the biscuit mixture firmly into the base of the springform cake tin. Refrigerate the base for 20 minutes.

Whisk 4 egg yolks with 80 g granulated sugar and 30 g cornflour until smooth. Heat 300 ml whole milk with the split vanilla bean until steaming.

Gradually whisk the hot milk into the egg mixture. Return the mixture to the saucepan.

Cook the custard over medium heat while whisking until thickened. Remove the saucepan from the heat.

Stir 4.5 bloomed gelatine sheets into the hot custard until dissolved. Add 130 g white chocolate and stir until melted.

Remove the vanilla bean and sieve the custard into a bowl. Cool the custard to room temperature, stirring occasionally.

Whip 300 ml heavy cream to soft peaks. Fold the whipped cream into the cooled custard to make diplomat cream.

Hull and slice 500 g fresh strawberries. Arrange the sliced strawberries around the inside edge of the chilled biscuit base.

Spread 145 g strawberry jam over the biscuit base. Spoon the diplomat cream into the tin and level the surface.

Refrigerate the assembled cake until set, for at least 4 hours. Keep it chilled until decorating.

Whip 200 ml whipped heavy cream with 15 g icing sugar until firm peaks form. Pipe or spread the sweetened cream over the chilled cake.

Decorate the cake with the remaining fresh strawberries and crushed butter biscuits. Add small spoonfuls of strawberry jam before serving.