Sadly my Simnel Cake cake sunk on cooling. Perfect when it came out of the the oven, would welcome feedback?
Nigella's Simnel Cake (from FEAST) is a light fruit cake. In the UK it was traditionally associated with Mothering Sunday (the fourth Sunday in Lent), but now is more often baked for Easter. There are a couple of common reasons why the cake may have sunk and usually it is as the cake is not quite fully baked. The cake should be risen and firm on top and shrinking away slightly from the sides of the tin. It is slightly difficult to use a cake tester as the layer of marzipan in the centre will be a little gooey.
The other reason is that too much leavening may have been used, causing the cake to rise up a lot in the oven and then sink back on cooling. The cake doesn't have much leavening and make sure it is a level 5ml teaspoon of baking powder. Also the flour should be plain (all-purpose) and not self-raising. If the cake has sunk a little you can flip it over so that the base becomes the top and gives a flat surface for the marzipan coating.