- 6 eggs
- 1/2 cup freshly grated Parmesan cheese
- Salt and freshly ground black pepper
- 3 tablespoons olive oil
- 1/2 small red onion, chopped
- 1 pound fresh spinach, chopped
- Position the rack under a broiler 4 inches from the heat source and turn it to high.
- Crack the eggs and open them into a bowl.
- Add the cheese, sprinkle with some salt and pepper, and whisk until the yolks and whites are combined.
- Put 1 tablespoon of the olive oil in a skillet, over medium-high heat.
- When hot, add the onion, sprinkle with salt and pepper, and cook until soft, 3 to 5 minutes.
- Add the spinach and cook, stirring and tossing frequently, until the leaves wilt and release their liquid; lower the heat if necessary to keep everything from burning.
- Once the spinach starts to dry and stick to the pan, after 3 to 5 minutes, turn the heat to low.
- Cook, stirring occasionally, until there is no water left in the pan and the spinach is coated in oil, another minute, then spread out the spinach in the pan.
- Pour the egg mixture over the spinach and onions, evenly distributing the vegetables if necessary.
- Cook, undisturbed, until the eggs are firm at the bottom and the top is still runny, 8 to 10 minutes.
- Put the pan under the broiler until the eggs finish setting and brown lightly, 2 to 4 minutes, watching to make sure the frittata doesn't burn.
- Cut the frittata into wedges and serve right away, or warm, or at room temperature.