Plum and Apple Cake

• 2 eggs, separated
• 5 oz / 140 g light muscovado sugar

Beat the egg yolks and sugar together until pale and foamy. Whisk the egg whites to firm peaks. Mix the yoghurt and oil into the egg and sugar, and then add the fruit. Sift the dry ingredients together, and stir into the mixture, finally folding in the egg whites. Pour into a greased 8 or 9 in /