Have a serving plate ready by the stove. Heat butter in a small nonstick omelet pan over high heat, tilting the pan to coat the entire surface.
Pour egg mixture into pan and scramble it with the back of a fork or wooden spoon as you gently shake the pan. Keep moving the pan and utensil at the same time until the egg mixture has coagulated and is nearly set, 2-3 minutes. Gently press the eggs down into an even layer and top with the cheese.
Lower the heat and let the egg mixture finish cooking without stirring, 15-20 seconds. Sprinkle with the herbs.
Tilt the pan and slide a fork or spoon under the omelet, to be sure it is not sticking. Slide the omelet to the front of the pan and use a fork or a wooden spoon to roll the edge nearest the handle toward the center of the omelet. Tip the pan, rolling the omelet onto the serving plate. To give the omelet additional sheen, rub the surface lightly with butter.
Makes 1 serving