Peel or clean and wash the soup greens and peppers. Dice everything finely. Peel and finely chop onion and garlic
Heat the oil in a pan. Sauté the onion and garlic in it. Add the diced vegetables and steam for 3-5 minutes. Season with salt and pepper. Add tomato puree and sauté briefly. Dust with flour. Add 1/8 l water and tomatoes. Bring to the boil and simmer for 6-8 minutes. Stir from time to time
Cook the spaghetti in plenty of boiling salted water for 8-10 minutes until al dente. Slice or grate Parmesan cheese. Wash basil, cut leaves into fine strips and stir into the sauce. Drain the pasta and serve immediately with sauce and parmesan