Recipe credit: https://tubtotable.com/

INGREDIENTS

  • 4 tablespoons butter
  • 1 large onion, diced
  • 4 cups chopped mustard greens (stems discarded and leaves coarsely chopped)
  • 8 eggs, beaten
  • 1/4 cup heavy cream
  • Kosher salt and freshly ground pepper
  • 1 cup grated Parmigiano-Reggiano

DIRECTIONS

  1. Preheat the oven to 350°.
  2. In a large ovenproof skillet, heat 3 tablespoons of the butter. Add the onion and cook over medium heat until translucent.
  3. Add the mustard greens and cook until wilted.
  4. Season the eggs with salt and pepper, whisk in the remaining tablespoon of butter and the cream.
  5. Pour the eggs into the skillet, tilt the pan so it the eggs are evenly distributed and cook over moderate heat for about 10 minutes.
  6. At this point the bottom and sides should be setting but the top should still be runny.. Sprinkle the Parmigiano-Reggiano on top.
  7. Transfer the skillet to the oven and bake for about 10 minutes, until the center of the frittata is set and slightly browned. Slide the frittata onto a cutting board.
  8. Cut into 1 1/2-inch squares and serve hot, warm or at room temperature. Also great as leftovers, reheated and served on a slice of toast.