1. Chop the onions.
2. Chop the bell peppers and tomatoes into large dice.
3. In a large pot, heat the olive oil. Add the onions and bell peppers. Sauté over medium heat for 6 minutes. Add the tomatoes. Reduce the heat, cover the pot, and simmer for 20 minutes.
4. In a large quantity of boiling salted water, cook the spaghetti al dente.
5. Drain the pasta. Transfer to a large bowl. Add the vegetable compote and basil. Serve immediately.