Mix both types of flour and baking powder. Eggs are broken sugar foam. Add the yogurt, mixed with soda, the butter and lemon zest. The dough is poured into a wide pan on baking paper. Bake at 180C for about 20 minutes or until lightly browned. Allow to cool. Peel apples and cut into small pieces. Put them in hot butter with cinnamon stick and add the sugar, lemon juice and zest. While apples stew starch dissolved in apple juice and add to them. Stir until thickened. Allow to cool. The cream was stirred and added to half of the apple filling. The base is cut in two. With cream stuffing stick two parts and the above allocation of the remaining apple filling. If it is too thick, it can warm slightly in microwave or over low heat.