Here’s one way to get anyone to eat a pile of mini cabbages—sink them into a fluffy frittata, and then put a mountain-style avalanche of cheese on top.
Allergen Note: Contains milk, eggs.
Preheat the oven to 375°F. Trim and slice the Brussels sprouts. Slice about 1½ cups of shallots.
In a cast-iron skillet (about 10 inches) or ovenproof pan over medium heat, warm ¼ cup olive oil. Add the Brussels and shallots and sauté until soft and golden, 5 to 7 minutes. Season with salt and pepper.
Meanwhile, crack 8 eggs into a large bowl and whisk to combine. Stir in about 2 cups (6 oz) of cheese, 1 teaspoon salt, and a generous grind of pepper. When the vegetables are ready, add them to the egg mixture and stir to combine.
Wipe out the pan, return it to medium-high heat, and melt 1 tablespoon butter, tilting to coat the bottom of the pan. Pour in the egg-and-vegetable mixture and cook to let the bottom set, 1 minute. Transfer the pan to the oven and bake until lightly puffed, golden, and just set at the center, 12 to 15 minutes, depending on the size of the pan.
Let the frittata rest for a few minutes. Cut into wedges, transfer to plates, and serve warm.