Instructions

1. Position a rack in the upper third of oven, and preheat boiler to high.
2. Heat 1 tablespoon of oil in a large, cast-iron skillet over medium heat.
3. Add onion and cook, stirring occasionally, until starting to brown, 2 to 4 minutes.
4. Add cauliflower and water. Cover and cook until just tender, about 6 minutes.
5. Add kale, garlic, thyme and ¼ teaspoon each salt and pepper; cook, stirring often, until the kale is wilted, 2 to 3 minutes.
6. Whisk eggs, paprika and the remaining 1/4 teaspoon salt and pepper in a large bowl. Add the vegetables to the egg mixture; gently stir to combine.
7. Wipe the pan clean; add the remaining 1 tablespoon oil and heat over medium heat. Pour in the egg mixture and top with cheese. Cover and cook until the edges are set and the bottom is brown, 4 to 5 minutes.
8. Transfer the pan to the oven and broil until the top of the frittata is just cooked, 2 to 3 minutes.