This Spinach Frittata is a healthy and flavorful breakfast or brunch dish that combines the goodness of fresh spinach with the savory flavors of eggs, vegetables, and cheese. The frittata is made by sautéing spinach, onions, and garlic in a skillet, then pouring a mixture of beaten eggs and shredded cheese over the top. Baked until golden brown and fluffy, this frittata is a nutritious and easy-to-make meal that's perfect for any occasion.