Submitted by Sarah Fritschner
- 2 Tbsp extra-virgin olive oil
- 1 medium onion, diced
- 3⁄4 lb mustard, kale, spinach, or other greens, stems discarded and leaves coarsely chopped
- 8 large eggs, beaten
- 1⁄2 tsp each salt and pepper
- 1⁄3 C grated Parmesan or cheddar cheese
Preheat the oven to 350°. Heat a tablespoon of oil in an 8-inch cast-iron skillet (or similar). Add onion and cook over moderately high heat until golden, stirring occasionally, about 10 minutes. Add greens and cook until tender.
Season eggs with salt and pepper and beat with remaining oil. Pour into the skillet and cook over moderate heat until the bottom and sides begin to set. Lift the sides of the frittata to allow the uncooked eggs to seep under. Cook until bottom is set and top is still runny, 3 minutes. Sprinkle with cheese and bake about 5 minutes, until the center of the frittata is set. Serves 4.