Preheat oven to 350 degrees. In mixing bowl, combine eggs, milk, pesto, salt, pepper and Italian seasoning. Whisk well. In a skillet over medium heat, melt butter and sauté bell pepper and onion until softened 4-6 minutes. Pour pepper and onion mixture into pie shell. Top with cheese. Add egg mixture. Bake for 45-50 minutes, until center is set. Serves 6