First you melt the butter in a saucepan on medium heat and add the flour, which you then mix into a roux. When you have a solid mass, add the tomato paste and mix it with the finished roux until the solid mass is completely red through the tomato paste. This solid red mass is gradually poured over with warm water while stirring constantly (so that there are no lumps) until the tomato sauce has reached the desired consistency - at the end it should ideally be creamy and not too runny. Then add sugar, salt and pepper to the sauce. If you like it more tomato or sweeter, you can use more tomato paste, sugar, etc. if you like.
Classic pasta is served with `sweet` tomato sauce, of course, regardless of whether you use spaghetti, spirelli or whatever other pasta you have on hand. Cook these al dente according to the instructions on the packet.
Tips: This dish or sauce can be stretched to any number of people by increasing the quantities. I always calculate about 150 g of pasta per person.
Instead of filling the sauce with warm water, you can also use the pasta water from the pasta that is still boiling, which is the rule here.
The dish can also be reheated the next day without any problems.