recipe for spinach quiche

Ingredients 1 pre-made 9-inch pie crust (store-bought or homemade) 1 tablespoon olive oil 1 small onion, finely chopped 2 cloves garlic, minced 5 ounces fresh spinach, roughly chopped 4 large eggs 1 cup half-and-half (or whole milk) 1/2 teaspoon salt 1/4 teaspoon black pepper 1/4 teaspoon ground nutmeg (optional)