Why Did My Chocolate Fudge Cake Overflow From The Tin?

Our answer

Nigella's Chocolate Fudge Cake (from NIGELLA BITES) has a moist chocolate sponge and is sandwiched and topped with a chocolate fudge frosting. The cake batter is quite liquid but should not be too much for two 20cm (8-inch) cake pans or sandwich tins.

For the sponge you would need tins that are approximately 4.5cm deep. Some older sandwich pans are shallower and could be one reason why the cake batter overflowed during cooking. However, if the second sponge collapsed on cooling it usually indicates that there is a different issue. The cake has 1 teaspoon of bicarbonate of soda and 2 teaspoons of baking powder as the leavening agents. The reaction of the cake, as described, suggests that too much leavening was used. if it is too much bicarbonate of soda then the cake will tend to bubble up the sides and over the top of the tin as bicarbonate of soda creates a quick, bubbling reaction. Also, if too much or the wrong sort of leavening is used then the cake will rise too much during baking but collapse on cooling, as the glutens in the flour have been stretched too much to be able to hold any structure. We suggest using a 5ml/1 teaspoon measuring spoons to measure the leavening and use level spoon measures. Also check that the correct amounts of each type of leavening have been used.