1 teaspoon olive oil or canola oil1 cup chopped onion4 small (6-inch) zucchini, thinly sliced2 medium tomatoes, chopped Freshly ground pepper Grated Parmesan cheese (optional) In a large, nonstick skillet, heat oil over medium heat; add onions and cook, stirring until softened. Add zucchini and cook for two minutes. Add tomatoes and cook for three to five minute...