Pre-heat your oven to 160C Fan/180C/350F/Gas Mark 4, and grease and line three 8" cake tins that are at least 2" deep
Make the sponge by mixing the butter and caster sugar in a large bowl until fluffy, ideally using an electric mixer
Add the eggs and milk, and whisk until fully incorporated
Add the cocoa powder, baking powder and self raising flour and whisk in gently until you can't see any flour anymore
Divide the mixture between the tins, use scales for accuracy if you like
Bake them for 30-35 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 knife
To make the buttercream, mix together the butter and peanut butter until smooth. Then add the cocoa powder, icing sugar and milk, for best results use an electric mixer
Whisk until smooth, you can add extra milk if the buttercream is too stiff
Stack the sponges up on your plate or cake stand, piping or spreading buttercream between each layer. Drizzle the caramel over each layer of buttercream, and sprinkle some peanuts on top
When you get to the last layer, pipe larger rosettes all around the edge and smaller ones in the centre, drizzle over more caramel sauce and add some peanuts too
Add the chopped Snickers pieces all around the edge
Serve immediately, store leftovers in an airtight container in a cool place and eat within 3 days
Video
Notes
Make sure all your ingredients (particularly the butter and eggs) are at room temperature before you start baking.
I used a baking spread for the cake and unsalted butter for the buttercream.
If you can't get hold of Snickers bars, you could decorate the top of the cake with more peanuts.
I used roasted salted peanuts for the cake, the salt cuts into the sweetness of the cake and it give you salted caramel vibes!
You can use any cocoa powder for this cake, of course the better quality it is, the better flavour it will have. Also do make sure you are using cocoa powder and not a hot chocolate powder.
Although I provide cup measurements, I highly recommend weighing your ingredients out using digital kitchen scales*. It is the most accurate way to measure ingredients and will ensure the best results. Digital scales are very low cost and can be purchased for around £12 ($16.50) .
For teaspoon (tsp) and tablespoon (tbsp) measurements, please use measuring spoons* and not the type of spoons you eat with. Again this will ensure accuracy and provide the best results.
For a two layer cake, use 335g of butter, 335g caster sugar, 6 eggs, ½ tbsp milk, 285g self raising flour, 50g cocoa powder and ⅛ tsp baking powder. For the buttercream, 230g butter, 365g icing sugar, 85g peanut butter, 1-2 tbsp milk and 35g cocoa powder.For a one layer cake use 175g of butter, 175g caster sugar, 3 eggs, ¼ tbsp milk, 140g self raising flour, 25g cocoa powder and a pinch of baking powder. For the buttercream, 115g butter, 180g icing sugar, 40g peanut butter, ½ - 1 tbsp milk and 18g cocoa powder.