Hard scrambled eggs, when done right, are creamy, firm, and yet fluffy. They are a masterpiece of simplicity. A hard scramble is the kind of eggs found in American diners.
Crack eggs into a medium bowl and whisk together until the mixture is pale yellow; about 30 seconds.
Melt butter in an 8-inch non-stick skillet over medium-low heat. When butter begins to foam, about 30 seconds, add eggs.
Cook the eggs, stirring and pulling the mixture across the pan with inverted turns, forming large soft curds. Continue pulling, lifting, and folding the eggs until no visible liquid remains. About 5 minutes.
Season the eggs with salt and pepper. You can also do this when whisking them.