Tomato and Basil Frittata

• 2 Tablespoons olive oil
• 2 medium onions, thinly sliced
• 1 cup canned Italian tomatoes, drained and chopped
• 6 eggs, beaten
• 1/2 cup chopped fresh basil
• 2 Tablespoons freshly grated Parmesan cheese
• Salt and freshly ground pepper to taste
• 2 Tablespoons butter

Instructions:
Heat the oil in a medium skillet over moderate heat and saute the onions until golden but not brown. Add the tomatoes and cook for 5 minutes, stirring frequently. Transfer the onions and tomatoes to a bowl and allow to cool slightly. Add the eggs, basil, Parmesan cheese, salt, and pepper to the bowl and mix well. Melt the butter in a 12-inch skillet over moderate heat. Add the egg mixture and turn the heat as low as possible. Continue cooking uncovered and without stirring until all but the top of the egg mixture has set, about 15 minutes. Place the skillet under a preheated broiler for 1 to 2 minutes, until the top is set. The frittata should not be brown, either on the top or the bottom. Cut into wedges to serve.
Serves 4 to 6.