• Preheat the oven to 350F/180C.
• Grease and flour three 9" cake pans. You can also use 8" pans for a taller cake.
• In a large saucepan heat stout, coffee and butter together until the mixture comes to a gentle simmer.
• Add cocoa powder while whisking continuously to avoid lumps Beat until smooth. Put it in the fridge to cool.
• Blend flour, sugar, baking soda, and salt in a different bowl.
• In a third bowl, mix eggs, vanilla and sour cream with an electric mixer.
• Once chocolate mixture is cool, add it to the egg and sour cream mixture. Mix them together.
• Add flour mixture a little bit at a time and beat on low speed until combined.
• Divide batter equally among the pans.
• Bake cakes in the preheated oven for 30 minutes.
• Remove the cakes from the oven and cool on a wire rack.

For the Salted Caramel Buttercream

• Whip butter in a bowl of a stand mixer until light and fluffy and then add dulce de leche along with a pinch of salt until completely incorporated.
• Wrap Butterfinger bars in a clean tea towel and crush with a rolling pin or process in a food processor.
• Fold in crushed honeycomb pieces into buttercream.
• Fill the cake layers with salted caramel buttercream, then cover the entire cake with remaining buttercream. Chill in the fridge for at least 60 minutes.

Chocolate Ganace

• Bring heavy cream barely to a boil.
• Remove from heat and pour over chocolate morsels. DO NOT MIX.
• Put a lid over it and let it sit for 15 minutes.
• After 15 minutes, whisk the mixture - starting from the inside and working your way out.
• Let sit for 15-20 minutes at room temperature until thick enough to spread on the cake.
• Cover the chilled cake with chocolate ganache and decorate with more honeycomb pieces and salt.