Hello, I would like to make a 9 inch square buttermilk birthday cake in one tin that I can cut in half and sandwich together, not two separate tins. Could you let me know quantities and baking time? Thank you so so much!
The recipe for Nigella's Buttermilk Birthday Cake (from Domestic Goddess) is enough for one 9 inch/23cm square cake tin. We would suggest that if you only have one tin that you make one cake, let it cool are remove it from the tin, then use the tin again to make the second layer.
Scaling cakes up is not a straightforward process and unfortunately we have not tested scaled versions of the Buttermilk Birthday Cake, except for the shaped cake mould versions mentioned by Nigella in the recipe introduction. If you just make one cake and slice it in half then the layers could end up being slightly skinny, and doubling the quantity of cake batter could lead to the cake overflowing from the tin. In addition, making a larger quantity of cake can lead to problems with the edges of the cake becoming burned whilst the centre of the cake remains undercooked.