Preheat the oven to 375°F (190°C).
In a large bowl, whisk together the eggs, milk, garlic powder, salt, and pepper.
Stir in the cottage cheese, spinach, mushrooms, mozzarella cheese, and Parmesan cheese.
Pour the mixture into a greased 9-inch pie dish.
Bake for 30-35 minutes, or until the quiche is set and golden brown on top.
Let cool slightly before serving.
