Clean, wash and cut the beans into short pieces. Cook in boiling salted water for about 8 minutes. Drain, rinse with cold water and let drain. Cook pasta in boiling salted water according to package instructions. In the meantime, wash the lemon hot, grate dry and finely grate the peel. Squeeze lemon.
Heat the oil in a large coated pan. Press the sausage meat from the skin as balls directly into the hot oil and fry it for about 3 minutes. Take out.
Heat butter in a pot. Lightly sweat flour in it. Stir in 200 ml water, lemon juice and cream. Bring to the boil and simmer for about 3 minutes. Season sauce with salt, pepper and 1 pinch of sugar. Keep sauce warm.
Wash and coarsely chop the basil. Drain the pasta and put it back into the pot. Add meatballs, basil, beans and sauce to the noodles. Mix everything and serve immediately.