In a medium bowl whisk the eggs, then add the cheese along with a pinch of salt and pepper. Stir to combine.

Heat an oven safe non-stick skillet or well seasoned cast iron skillet over medium heat then add a splash of olive oil and saute the onions until soft, brown and fragrant, about 15-20 minutes. If you're using a leafy vegetable, make sure you squeeze out any excess moisture with your hands. Add the vegetables to the pan and saute to warm.

Pour the egg and cheese mixture over the vegetables and stir to combine. Turn down the heat to medium low then smooth off the top and allow the egg to cook about half-way through. You can check to see how well cooked it is by tipping the pan up and shaking. It should be firm but jiggly, kind of like a pan of jello.

Move the oven rack to the upper middle position and turn the broiler on. Place the skillet under the broiler until the top is mostly set and is just starting to brown (1-2 minutes). Remove from the oven and allow to rest for 5 minutes. Slice and serve warm with a salad.