Mushroom and Cheese Frittata

Ingredients: 8 eggs ¼ cup 2% low-fat milk ¼ cup grated parmesan cheese 1 teaspoon dried sage ¼ teaspoon ground pepper 2 tablespoons olive oil or 2 tablespoons butter 1 medium onion, diced ½ cup red pepper (bell pepper), diced ±225g sliced small mushrooms 2 garlic cloves, minced 2 tablespoons minced parsley (optional) 3⁄4 cup…