Clean and wash the broccoli and cut it into small florets. Peel and chop the onion. Heat the oil in a large pan with a high rim. Put onion sausage meat in large pieces directly into the pan and fry it while turning.
Fry the broccoli and onion briefly.
Add the tomatoes and about 400 ml water. Stir in Harissa. Season everything with salt, pepper and 1 pinch of sugar. Break the spaghetti into pieces several times, put it into the pan and mix well. Bring to the boil and simmer for 8-10 minutes, stirring from time to time.
If the sauce gets too thick, add some more water.
Meanwhile grate the Parmesan finely and mix with sour cream. Stir about 1 tbsp. into the pasta. Season to taste with salt and pepper and serve. Add the rest of the sour cream.