-
1
Butter and flour a 25 cm non-stick ring or bundt tin (these are very popular with American cooks).
-
2
Bring the 200 ml cola to the boil with the 125 g butter, and once this has melted stir in the bicarbonate of soda which will fizz.
-
3
Set aside for 20 minutes,.
-
4
Preheat the oven to 190C/gas 5.
-
5
Combine the flour, 1 tbsp cocoa and sugar in a large bowl, add the coke mixture and whisk until smooth.
-
6
Whisk in the eggs wtih the buttermilk and vanilla exract, then whisk this into the cake base.
-
7
Transfer the mixture to the prepared tin and give it a couple of taps on the work surface to bring up any bubbles.
-
8
Bake for 35-40 minutes until risen and set and a skewer inserted at the centre comes out clean.
-
9
Run a knife around the inner and outer edges and leave to cool for about 30 minutes, then place a cake stand or plate on top of the tin and invert it.
-
10
Leave to cool completely.
-
11
To make the icing, place the 3 tbsp cola, 50 g butter and 1 tbsp cocoa in a small saucepan and bring to the boil, whisking until smooth, then stir in the icing sugar.
-
12
This starts to set quickly so without delay trickle it over the crown of the ring, letting it drip down the sides (the cake doesn't need to be completely covered) If wished decorate with chocolate stars or sprinkles and cola-bottle sweets.
-
13
Set aside for about an hour for the icing to set.
