- Preheat oven to 350°F (175˚C).
- Butter a 2-quart (2 liter) soufflé dish.
- Add 1 cup cheese, tilting dish to evenly coat the bottom and sides. Shake out any excess. Set dish aside in refrigerator.
- Place the sour cream in a large mixing bowl.
- Sift the flour into the sour cream, then whisk until well combined.
- Add the egg yolks, one at a time, whisking after each addition.
- Stir in salt, cayenne, chives, and remaining 2 cups cheese.
- In a large clean bowl (copper is ideal), vigorously whip the egg whites until stiff peaks form.
- Gently fold egg whites into the sour cream mixture.
- Pour the batter into the prepared soufflé dish and bake until soufflé has risen 2–3 inches above the rim and top is golden brown (1 to 1½ hours).
- Serve immediately.