Beat eggs with sugar until a homogeneous mixture. Add flour to which baking powder is complex. Add the oil and mix. Diced two medium apples. Greased pan with sunflower oil or butter. Pour half of the mixture into it. Put it on the apples and cover with the rest of the mixture. Sprinkle generously with coarsely chopped walnuts. Bake in preheated oven at 200-220 C. Sprinkle with powdered sugar.