Frittatas are a quick meal and perfect any time of day. Try them tonight with a simple green salad, then munch on leftovers tomorrow morning with a side of oatmeal or in a tortilla for a wholesome lunch.
Preheat oven to 375°F.
In a medium bowl, whisk together egg whites, egg, and skim milk until frothy; set aside.
Heat oil in a 10-inch nonstick frying pan on medium. Add garlic and onion and sauté for 3 to 4 minutes, until softened. Add spinach to pan, in batches if necessary, and cook, stirring frequently, until wilted. Season with salt, pepper and nutmeg.
Pour egg mixture into pan and drop ricotta by the tablespoonful over top. Cook for 3 minutes, until eggs begin to set on the bottom. Transfer pan to oven and bake for 8 minutes or until eggs are firm. Cut frittata into 4 wedges and serve immediately.