Fry the sausages in the hot germ oil. Then take it out and keep it warm. Peel the onion and cut into strips, grate the apple finely. Fry the onion and apple in the remaining frying fat until golden. Add tomato paste and sweat. Dust with curry, paprika and chili powder. Pour in 1/4 liter of water. Bring to the boil and add the stock. Stir in the sauce thickener and cook for 1 minute. Finally, season with salt, pepper and possibly with sugar.
Tip: add half a finely chopped chilli pepper for extra heat.