This cheesy frittata is the kind of dish—fast, flexible and easy to reheat—that Tom Valenti likes to have around for all kinds of holiday eating. "A frittata is just as good, or maybe better, at midnight," he says. More Breakfast Recipes
Preheat the oven to 375°. In a bowl, beat the eggs with the water and season with 3/4 teaspoon of salt and 1/2 teaspoon of pepper. Beat in the Gruyère and prosciutto.
Heat the olive oil in a large, nonstick ovenproof skillet. Add the potatoes and cook over moderately high heat, stirring occasionally, until tender and golden brown, about 7 minutes. Add the scallions and cook for 1 minute. Stir the egg mixture and add to the skillet. Stir to distribute the potatoes. Cook until the bottom is just set, about 3 minutes; lift the frittata to allow the uncooked eggs to seep underneath.
Bake the frittata for about 10 minutes, until nearly set in the center.
Preheat the broiler. Broil the frittata 8 inches from the heat for 1 minute, until the top is just beginning to brown. Cut the frittata into wedges and serve hot or at room temperature.
The unmolded frittata can be kept at room temperature for 4 hours.