Heat oven to 400°F

In a large bowl, whisk together the egg yolks, chives, salt, and pepper.

In a separate bowl, with an electric mixer on medium-high, beat the egg whites until stiff peaks form. Using a spatula, gently fold the egg whites into the yolk mixture.

Meanwhile, melt the butter in a large nonstick skillet over medium-low heat and tilt to coat the sides. Add the soufflé mixture and crumble the cheese over the top. Bake until the eggs are puffed and golden, about 10 minutes. Cut into wedges.