Pre-heat your oven to 160C Fan/180C/350F/Gas Mark 4, and grease and line two 8" cake tins (that are at least 2" deep)
Mix the butter and sugar together until fluffy, ideally with an electric mixer, or you can mix in a bowl with a wooden or silicone spoon
Add the eggs and vanilla extract, and whisk until fully incorporated
Add the cocoa powder, bicarbonate of soda, red food colouring, buttermilk and self raising flour, and whisk in gently until fully combined
Divide the mixture between the tins, use scales for accuracy
Bake them for 40 minutes or until a skewer inserted in the middle comes out clean. Leave them to fully cool either in the tins or on cooling racks
If the cakes have domed on top, level them off with a cake leveller or a serrated knife - you can use some of the crumbs from doing this for decoration
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
Put one of the sponges on your plate or cake stand, and pipe or spread a layer of the frosting over it
And the second sponge on top, pipe larger rosettes of buttercream all around the edge and smaller ones in the centre
Decorate with cake crumbs or sprinkles
Serve immediately, store leftovers in an airtight container in the fridge and eat within 3 days