Add the curry powder and hot Paprika. Stir one minute.
Add the crushed tomatoes, sugar, red wine vinegar, and salt to taste
Simmer until thickened, approximately 25 minutes.
Notes
And if you are suspicious: yes curry is a thing in Germany. Curry Sauce, Curry Wurst and Curry Ketchup are a 'big deal' over there. I would love to know why that is...)
Recipe by Celtic Celiac at https://www.celticceliac.com/german-potluck-with-bonus-curry-sauce-recipe/