Preheat oven to fan assisted 160C / 180C / 350F / gas 4.

Lightly grease two 20cm cake tins and line the bottom of the tins with greased baking paper.

Lightly beat the egg yolks and set aside. Teat the egg whites until they are nice and stiff and also set aside.

Melt the chocolate in a bowl over a pot of water, then remove from the heat and mix in the butter, sugar and flour. Then quickly mix in the egg yolks.

Slowly fold in the egg whites (approx 3 tbsp at a time) until all gone.

Split the mixture evenly into the cake tins and bake for 35 mins.

Remove the cake from the oven. It may seem a bit uncooked when it is first taken out of the oven but it firms up when cool. Let it cool in the tins for about 20 mins before transferring to a cooling rack.

Prepare the cake by spreading some whipped cream on the top of one of the cakes, then add on the raspberries, then sandwich it with the second cake. Spread some more whipped cream on top and serve.