Start by weighing out all of your ingredients and then pour the partially melted butter and sugar into a bowl and mix together.
Next whisk your eggs and vanilla extract into the mixture.
Sift your flour and cocoa powder through your sieve into the mixture and stir in.
Split the mix into 12 cases and put to bake for 25 minutes
Once your timer is up, take your cakes out of the oven and poke them with a cocktail stick or fork, if it comes out clean then your cakes are ready. Then leave them to cool.
When cooled, scoop out the middle section of the cake, ready for the buttercream filling.