Adapting the Buttermilk Birthday Cake

Asked by happymummy. Answered on 4th September 2014

Full question

Hi! I would like to use the Buttermilk Birthday Cake recipe for my dad's 70th. He loves coffee cake and I wondered if I might be able to adapt the cake to add the coffee flavour without making the mix too runny? Can you advise? Thanks.

The Buttermilk Birthday Cake is a great recipe and I would like to make a chocolate version of it. Would you suggest adding cocoa powder or melted chocolate? What quantity of cocoa powder or melted chocolate would you advise and would I then have to reduce the quantity of any other ingredients in the recipe? Many thanks, Deane-Mae

Our answer

Nigella's Buttermilk Birthday Cake (from Domestic Goddess) is a perennial favourite. The vanilla version is extremely good in its own right so we have not tried flavouring it however we suspect that it is possible to make chocolate and coffee versions. For a coffee version we would suggest adding some instant espresso powder (this is a fine powder and different from instant coffee granules, but should be available in most supermarkets).We suspect that 4 teaspoons of the espresso powder, added with the flour, will give a robust coffee flavour. For a more muted version use 2 teaspoons.

For a chocolate version of the cake we would prefer to use cocoa powder as adding melted chocolate will change the structure of the cake. You will need to substitute some of the flour for cocoa powder, but as cocoa powder has slightly different properties to flour you may need to add some extra leavening. We would try replacing 50g (1/3 cup) of the flour with 50g (1/2 cup) cocoa powder and increase the bicarbonate of soda (baking soda) from 1/2 teaspoon to 3/4 teaspoon. We would however emphasise that we have not tried either of these versions so can't guarantee the results.