Preheat oven to 375°F. Heat 1 tablespoon oil over medium high heat in a heavy 12-inch nonstick oven-safe skillet; add mushrooms. Cook, stirring until they begin to sweat and soften. Add salt, pepper, and garlic; stir until garlic is fragrant. Add spinach; stir until wilted. Turn up heat and let excess liquid evaporate from pan. Remove from heat. While mushroom-spinach mixture is cooking, beat eggs and milk in a large bowl. Stir in salt, pepper and cheese. Evenly distribute ingredients in pan; pour egg mixture on top. Place skillet into oven; cook for about 10 minutes until eggs are set. Remove from oven before eggs brown. While hot, slide frittata onto a cutting board. Slice into wedges; serve warm with fresh fruit. Makes 4 servings.
Tip: This will keep in the refrigerator for 3 days and can be served cold.
Approximate Nutrient Analysis per serving (not including optional Parmesan or salt to taste):
250 calories, 17 g fat, 4.5 g saturated fat, 375 mg cholesterol, 220 mg sodium, 9 g carbohydrate, 3 g fiber, 2 g sugar, 16 g protein