Coffee And Walnut Traybake

Our answer

Nigella's Coffee And Walnut Layer Cake (from KITCHEN) is Nigella's version of this popular cake, with ground walnuts in the sponge mixture and a coffee flavoured frosting.

The cake is a two layer 20cm/8-inch cake and this amount of batter should convert to a 23cm/9-inch square cake tin that is aproximately 5cm/2 inches deep. If you wanted to make a larger cake in a rectangular tin, or roasting pan, approximately 32.5cm x 23cm x 4cm/13 x 9 x 1½ inches then you should need 1.5 times the recipe quantity. Line the base and sides of the pans with baking parchment (parchment paper). The baking times will be slightly longer and we suspect the square cake would take 30-35 minutes, but start checking after 25 minutes, and the rectangular cake approximately 35 to 40 minutes, though start checking after 30 minutes. We would suggest scaling the frosting ingredients along the same lines as the cake batter (i.e. 1x for the square cake and 1.5x for the rectangular cake). However we would mention that as we have not tried the cake in either of these forms, we are unable to guarantee the results.