How to make
Peel the onion and apple, grate or chop them finely and fry the onion in the butter first, then after a few minutes add the apple.
Add the tomato paste and starch dissolved in water. Season with salt and black pepper. Boil and stir to thickening.
Allow to boil for 10 minutes on low heat and then add the sugar. Use the sauce to season meats and pasta.
