In a small pan, heat 1 tbsp olive oil over medium-low heat. Add tomatoes and garlic and allow to lightly simmer while preparing the frittata. Reduce heat, and mix in fresh basil for the last 5 minutes of cooking.
Frittata
Preheat oven to 350 degrees. In a large nonstick skillet, heat 1 tbsp olive oil over medium heat. Saute onions, mushrooms, and bell peppers until cooked through, about 10 minutes. Season lightly with salt and pepper. Reduce the heat to medium low.
Separate the egg whites and yolks into two bowls. Whisk separately and then combine in one bowl. Mix in parmesan and parsley.
Pour the egg mixture into the nonstick skillet over the sauteed vegetables. Cook about 10-15 minutes over medium-low heat,stirring frequently, until the eggs just begin to firm up. Transfer to the oven for 10 minutes until the eggs are completely set.
Spoon the tomato-basil topping onto the frittata. Garnish with additional parmesan if desired and serve right away.