Heat the olive oil in a large skillet over medium heat. Add the onion, garlic, and broccoli and cook for about 5 minutes, stirring occasionally. Remove from heat and set aside.
In a large bowl, whisk together the eggs, salt, and pepper. Add the cooked vegetables and grated cheese and mix everything together.
Pour the mixture into a greased 9-inch baking dish and bake for 25 minutes, or until the frittata is set and the top is golden brown.
Let cool for a few minutes before serving.
Interesting Facts
Broccoli is a great source of Vitamin C, Vitamin K, and fibre.
Frittatas can be served warm or chilled.
You can customize this frittata by adding other vegetables, herbs, or spices.