For The Cake For The Filling

1. Before starting, take out the butter to let it reach room temperature.
2. Set the oven to 190°C/375°F/gas 5. Then grease two springform cake tins (roughly 20cm in size) with butter. Next, line the bottom with greaseproof paper and dust the sides with gluten-free flour.
3. In a bowl, beat the butter and sugar for around 5 minutes, or until the mixture is light and fluffy in consistency. Add the eggs one at a time, then stir in the vanilla extract until evenly combined. Sift the flour, baking powder, xanthan gum, and cocoa powder into the bowl, then fold them in. Add the milk and stir briefly until you have a smooth batter.
4. Carefully divide the batter between the cake tins. Then, place them on the middle shelf of the hot oven for 15 to 20 minutes or until a skewer inserted into the center comes out clean. After baking, let them cool in the tins for 5 minutes. Next, turn the cakes out onto a wire cooling rack and let them cool completely while you prepare the icing.
5. Sift the icing sugar and cocoa powder into a large bowl. Then add the butter and beat until smooth. Stir in the cream cheese until combined. If the mixture is too thick, add a splash of milk to loosen it up.
6. Once cooled, put one of the sponges on a plate or a cake stand. Carefully spread half of the butter icing over the sponge. In a bowl, crush the raspberries with a fork and then scatter them on top. Place the second sponge on top and press down slightly. Finally, spread the remaining icing over the top and decorate it with chocolate shavings.