Crack the warm eggs into a bowl, add salt and beat with a fork. Heat a 10-inch nonstick aluminum pan over medium heat.
Once the pan is hot, add the butter and use a pastry brush to brush the butter around the surface of the pan. Pour the eggs into the center of the pan and stir vigorously with a rubber spatula for 5 seconds. As soon as a semi-solid mass begins to form, lift the pan and move it around until the excess liquid pours off into the pan. Using your spatula, move it around the edge of the egg mixture to help shape into a round and loosen the edge. Let the omelet sit in the pan for 10 seconds without touching.
Shake the pan to loosen the egg from the pan. Lift up the far edge of the pan and snap it back toward you to flip the omelet. Using your spatula, fold over one-third of the omelet. Slide the omelet onto a plate and fold over so that the omelet is a tri-fold. Coat with the remaining butter and sprinkle with the chives. Serve immediately.