Kale, Potato, and Onion Frittata

Ingredients
Makes 4 servings
Vegetable oil cooking spray
1 yellow or white onion, sliced
1 pound kale, trimmed, blanched 3 minutes in boiling water, drained, squeezed and coarsely chopped
2 cloves garlic, chopped
2 cups boiled diced potatoes
2 whole eggs
2 egg whites
1/2 teaspoon paprika (preferably smoked)

Heat oven to 400°F. In a medium skillet coated with cooking spray, cook yellow onion over medium heat, stirring, 5 minutes. Add kale and garlic; stir 5 minutes. Add potatoes. Whisk eggs, egg whites, 2 tablespoon water and paprika in a bowl. Stir in kale-potato mixture. In a cast-iron skillet coated with cooking spray, cook egg mixture over medium-low heat 1 minute. Transfer skillet to oven; bake until eggs are set and center is slightly runny, 6 to 8 minutes. Broil until top is golden, 1 minute.

Source: https://www.epicurious.com/recipes/food/views/kale-potato-and-onion-frittata-363789