Step 1

Preheat oven to 190°C (170°C fan). Butter 3 x 20cm round springform cake tins and line bases with baking paper.

Step 2

To make cakes, place butter and sugar in a bowl and use an electric mixer to beat until light and fluffy.

Step 3

Add eggs, one at a time, making sure the first is well incorporated before adding the next.

Step 4

Add flour in 3 batches, alternating with half the buttermilk, beginning and ending with flour. Add salt, vanilla and cocoa.

Step 5

In a separate bowl, combine vinegar and bicarb, then beat into batter.

Step 6

Divide mixture between tins. Bake for 20-25 mins, or until cakepulls away from sides of tins and a skewer comes out clean. Cool on a rack for 10mins, then turn out to cool completely, right-side up.

Step 7

To assemble, spread half the chocolate cream on first layer, then place second layer on top and spread with remaining chocolate cream. Place third layer on top.

Step 8

Place chocolate in a bowl and set over a saucepan of simmering water. Making sure base of bowl doesn't touch water.

Step 9

When chocolate is nearly melted, remove bowl to a cool surface and stir until chocolate has melted completely and starts to cool.

Step 10

Beat sour cream into chocolate, cover with plastic wrap and refrigerate for 2 hrs.

Step 11

Melt chocolate and butter in a small saucepan over low heat. Stirring until smooth. Stir in coffee mixture.

Step 12

Spread icing over top of cake with an offset spatula. Leave to set for 1 hour.