The plum cake is a delicate and delicious treat, perfect for the whole family, made with just a few really simple ingredients. If you are fortunate enough to have a plum tree in your garden you can collect as many as your inclination demands, and use them not just for baking cakes but also for making tarts, jams, preserves and any other recipe which your imagination might dream up. Otherwise, head to your favourite greengrocer and stock up with your preferred variety: ordinary plums are perfect for this cake, but you could also try some more unusual varieties, or use damsons - or even substitute another fruit altogether, such as peaches.
Beat the egg yolks with the sugar until the mixture is smooth and fluffy. Add the flour, baking powder and softened, chopped up butter. Beat well together. Then add the milk and yoghurt and work into the mixture again. Separately, beat the egg whites until they are firm and holding peaks. Incorporate these into the mixture, folding them in gently from the bottom to the top. Now pour the mixture into a buttered and floured cake tin. Wash the plums, dry them well, cut them into thin slices and arrange them radially on the surface of the cake. Bake at 180°C for 30 minutes.