Pre-heat your oven to 160C Fan/180C/350F/Gas Mark 4 and line a cupcake tin with cupcake cases
Mix the butter and sugar together until fluffy, ideally with an electric mixer for the best results
Add the eggs and vanilla extract, and mix in well
Add the cocoa powder, bicarbonate of soda, red food colouring, buttermilk and self raising flour, and mix in gently until fully combined
Divide the mixture between the cupcakes cases, and bake them for 20-25 minutes or until a skewer inserted in the centre of the cupcakes comes out clean. Put them on a rack to cool completely
To make the cream cheese frosting, use an electric mixer to beat the butter until smooth. Then mix in the icing sugar until the mixture is smooth
Next, add the cream cheese and the vanilla extract and mix in until the frosting is thick and smooth. Be careful not to over mix as this can make the frosting sloppy, and you won't be able to get it thick again
If you want to decorate the cupcakes with cake crumbs, level off a couple of the cupcakes and crumble up the pieces
Pipe or spread the frosting on top of the cupcakes, then add sprinkles of your choice, or cake crumbs
Store in the fridge and eat within 3 days