Why Did My Chocolate Fudge Cake Sink?

Our answer

Nigella's Chocolate Fudge Cake (from NIGELLA BITES) has moist chocolate sponge layers that are sandwiched and coated with a rich, fudgy buttercream icing. The cake batter itself is quite liquid as it contains both sour cream and water, but this helps to make sure that the sponges are moist and tender.

If the sponges have sunk after baking, there could be a variety of reasons. Most common is that the cake was not quite fully baked when it was removed from the oven and this will cause it to sink as it cools. If the cake was rising a lot in the very centre (forming a peak) then it is often an indicator that the oven was too hot, meaning that the cake rose and formed a crust on top but was not fully set in the centre. If you are using a fan oven then you may need to reduce the oven temperature slightly more than the usual 20c, as some fan ovens still cook very quicky even after using a standard fan oven setting - your oven handbook may have some guidance. The sponges should feel firm to the touch, be slightly shrinking away from the sides of the pans and a cake tester inserted into the centre should come out clean. If the cakes rose a lot when baking and then collapsed, then sometimes this can be caused by too much raising agent. The surface of the cake will usually be very wrinkled once it has cooled if this is the reason. Measure the baking powder and bicarbonate of soda (baking soda) carefully, using a 1 teaspoon (5ml) measuring spoon and only use level teaspoon measures. Also, make sure that you use plain (all-purpose) flour and not self-raising flour.