French Onion Soup Frittata

Makes 4–6 servings.


  • 1 lemon, zested
  • 8 large eggs
  • 1/2 c. half and half or milk
  • 3/4 tsp. kosher salt
  • 1/4 tsp. black pepper
  • 2 Tbsp. olive oil
  • 1 Tbsp. butter
  • 1/2 medium yellow or sweet onion, thinly sliced
  • Salt and pepper, to taste
  • 2 tsp. Herbes De Provence or Italian Seasoning
  • Splash of white or red wine vinegar
  • 1 medium (8 oz.) russet potato, peeled, cooked and cut into medium dice or 8 oz. baby potatoes (Dutch or pee-wee)
    If using baby potatoes and they are large, cut in half or fourths
  • 1 c. loosely measured (about 1 handful) of Tuscan kale, thick stems removed and roughly chopped
  • 1/4 c. Emmentaler cheese, grated


Preheat oven to broil, adjusting oven rack to top third of oven. Do not use the top slot.

In medium bowl, whisk to combine lemon zest, eggs, milk, salt and pepper.

Heat a large, nonstick, oven-proof sauté pan or cast iron skillet (9–10 inches) over low/medium heat. Add oil and butter; when hot, add onion, salt, pepper and Herbs de Provence. Sauté, stirring often, for 7 minutes, or until onions are very soft and lightly browned around the edges. If onions are browning too quickly, turn down heat. Add splash of vinegar, cooked potatoes and kale; stir to combine. With a spatula, move onions, potatoes and kale to distribute evenly across the surface of the pan.

Reduce heat to low and pour in egg mixture. Wait 1 to 2 minutes and then, using edge of spatula, carefully pull cooked sides in towards center to allow uncooked egg to flow to the outside edges. Repeat until very little moisture remains on top, about 4 to 5 minutes.

Sprinkle with Emmentaler cheese and place under broiler for 3 to 5 more minutes until slightly browned and puffed. Watch closely to prevent burning.

Serve warm.


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Recipe and photo courtesy of Chef Louise Mellor, “Geez Louise!”