Step 1: For making skin:
Preheat the oven at ± 200° C. Boil water, salt and margarine at low heat until boiling. Add flour, stir well until it does not stick on the pot. Turn off the stove, let it cool. Then add the egg one by one and stir well. Using pipping bag and tip, place the dough on a tray which has been layered with some margarine, gives enough space in between. Bake it in the oven for 30minutes. Do not open the oven door before it is done. Cool it down on a wire rack.
Step 2: For filling:
Mix all of the ingredients except butter. Cook in a pot and stir until boiling. Remove it from the heat and add the butter and stir until all melted. Let it cool and stir it once awhile.
Step 3: To serve, cut the skins in the middle and then fill it out with the filling. You may add some fresh/canned fruits into the filling as preferred.