Preheat oven to 400 degrees
Melt coconut oil in skillet
Add mushrooms, peppers, and spinach and cook until soft
Drain liquid from skillet and set aside
Whisk eggs, milk, parsley, garlic, salt, black pepper, and any additional spices in a bowl
Gently combine goat cheese into veggie mixture
Spread veggie/cheese mixture in prepared pie crust
Pour egg mixture evenly over the filling
Top with shredded mozzarella cheese
Bake in preheated oven until the quiche is lightly puffed and browned, 45 to 50 minutes (Toothpick inserted into the center of the filling should come out clean)
Cool for 30 minutes before serving