Peel and finely dice the onions and garlic cloves. Slice, wash and drain leeks.
Heat the olive oil on a pan, and fry the garlic, onion and leeks until soft, stirring occasionally. Add the drumsticks and cook until golden on all sides.
Meanwhile, wash, deseed and dice the tomatoes. Season the drumsticks with 2 tsp salt, add the chopped tomatoes and the tomato and basil sauce, stir, and let it cook with the lid on, for about 25 minutes.
Meanwhile, bring water to a boil in another pan, season with 1 tsp of salt, and add the spaghetti. Stir with a fork, bring back to a boil, and let it cook for no longer than 7 minutes, until al dente.
Wash the peppers and add them to the pan with the drumsticks. Let it cook for an additional 5 minutes, remove from heat, and add some fresh basil leaves.
Drain the spaghetti and serve with the chicken drumsticks.