Wash the apples and remove the core. Mix the almonds, raisins, jam and cinnamon and place in the opening of the apples with a teaspoon and press in with the handle of a wooden spoon.
Place the apples in a greased baking dish and put a flake of margarine on each apple. Bake in a preheated oven at 200 ° C (gas: setting 3, convection 175 ° C) for approx. 25 minutes.
For the sauce, mix the cornstarch and egg yolk in 2 tablespoons of cold milk. Bring the rest of the milk with sugar and vanilla sugar to the boil. Pour in the mixed cornstarch while stirring and let it boil briefly.