1. Saute onion for 5 minutes.
2. Add chopped pepper and sliced mushrooms, and saute 5 minutes more.
3. Add chopped garlic and chopped zucchini and saute 2 minutes more.
4. Add tomatoes, vinegar, sugar, and seasonings and bring to a boil.
5. Simmer about 30 minutes.
6. Add chopped fresh basil.
7. Adjust seasonings to taste.

Serve with bread and salad.