Preheat the oven to 180°C.
Grease 2 x 20 cm x 3 cm round cake tins with non-stick spray, then line the bases with baking paper.
Note: We made a 5-layer cake. To do so, double the recipe for the batter and icing and use 5 cake tins. Do not double the recipes for the butterscotch sauce and caramel chocolate shards.
Using a hand-mixer or wooden spoon, cream the butter and sugar until pale and fluffy. Add the eggs one at a time, while whisking, until incorporated.
In a separate bowl, mix the milk stout or beer and cocoa.
Sift the flour, baking powder and bicarbonate of soda together, then add, alternating with the egg mixture, to the milk stout-and-cocoa mixture.
Pour the batter into the tins and bake for 30 minutes, or until a skewer inserted comes out clean.
Allow the cakes to cool slightly before turning them out and cooling further on a wire rack.
To make the butterscotch sauce, place the sugar into a pan over a medium heat and allow to melt. When it is slightly caramelised, add the butter and mix until melted.
Bring to a gentle simmer, then remove from the heat and add the cream. Mix until smooth.
To make the caramel chocolate shards, melt the chocolate in a bowl over a saucepan of simmering water.
Pour the melted chocolate onto a non-stick baking mat or silicone paper, smooth out, then roll up the baking mat or paper and tie with string so it doesn’t unroll.
Chill for 15 minutes, then unroll the mat or paper, breaking off large shards of chocolate.
To make the dark chocolate icing, place the butter into a mixing bowl and cream lightly with a hand-mixer or wooden spoon. Add the icing sugar, a little at a time, and mix.
Add the milk and mix. Melt the chocolate and add slowly until the mix is even in colour and smooth.
To assemble the cake, spread some dark chocolate icing over one cake, then top with the other and spread with more icing. Pour over the butterscotch sauce and top with the caramel chocolate shards.
Use good-quality caramel chocolate such as Valrhona Caramelia to make the caramel chocolate shards.
This cake was baked in a fan-assisted oven. All ovens differ, so be sure to test the cake with a skewer before removing from the oven.
Buy ingredients online at Woolworths.