I just tried out the Apple and Almond Cake - it looked fantastic - a potential prize winner at a local baking contest. But it was very disappointing in texture - more like meat loaf. Dense, dense, dense. Surely it needs some agent such as baking powder to get some air into the mix?
Nigella's Apple And Almond Cake (from FEAST) is a gluten- and dairy-free cake that is made with apple puree. The cake itself does not contain any chemical leavenening, such as baking powder or bicarbonate of soda (baking soda), though the high proportion of eggs helps to give the cake a little lift.
The cake consequently has a closer texture than a traditional sponge cake, though this is not uncommon for gluten-free cakes, and it is best served warm as a pudding-type cake. The lack of leavening also makes the cake suitable for Passover. You could try adding some baking powder to the cake batter, however bear in mind that this could cause the cake to rise and then sink in the centre when it cools. An alternative, though more fiddly, way to make the cake could be to separate out two or three of the egg whites before making the batter. Whisk the whites to soft peaks and then fold them into the cake batter before the batter is poured into the cake tin. This should add a little extra lift to the cake, though as we have not tried this method we are unable to guarantee the results.