Gruyere Puff

3 large eggs
? cup whole milk
? cup all-purpose flour
? teaspoon kosher salt
Freshly ground black pepper
? cup grated Gruy?re cheese (about 3 ounces)
3 tablespoons unsalted butter
Coarse sea salt, for sprinkling.

Preheat oven to 400 degrees.

Whisk together eggs, milk, flour, salt and pepper in bowl until smooth. Stir in cheese.

In 9-inch ovenproof skillet, melt butter. Swirl to coat all sides. Pour in batter. Transfer to oven. Bake until puffed and dark golden, 30 minutes. Sprinkle with salt, serve hot.

from the New York Times food section.