A frittata is a simple baked egg dish that can include any combination of vegetables and cheese. This version includes fresh tomatoes, spinach, basil, and creamy ricotta cheese. Pair it with a salad for a quick weeknight dinner or prepare it ahead of time for a lower carbohydrate breakfast option.
Heat oven to 350 degrees. Heat oil in a large frying pan and cook the onion for 5-6 mins until softened and lightly golden. Add the tomatoes and toss for 1 min to soften.
Remove from the heat, add the spinach leaves and basil, and toss together to wilt a little. Transfer all the ingredients to a greased 13 by 9 inch rectangular baking pan. Alternately, you can use a 9- or 10-inch cast iron skillet to sauté vegetables and cook your frittata. Take small scoops of the ricotta and dot over the vegetables.
Season the eggs and beat well, then pour over the vegetables and cheese. Cook in the oven for 20-25 mins until pale golden and set.