Crack the egg whites into a mixing bowl and let them sit at room temperature for about 10 minutes to help achieve better volume.
Whisk the whites gently with a fork or whisk until they become frothy and slightly bubbly, about 30 seconds. Stop before they form stiff peaks to keep the omelette tender.
Heat a non-stick skillet over very low heat, approximately 70°C (158°F). Add a teaspoon of oil or butter, swirling to coat the bottom evenly.
Pour the whipped egg whites gently into the skillet, spreading them out evenly. You should hear a soft sizzle as they begin to set around the edges.
Allow the whites to cook undisturbed for about 2–3 minutes. You'll see tiny bubbles forming and the whites turning opaque around the edges.
Use a silicone spatula to gently lift and fold the edges inward, tilting the pan slightly so uncooked whites can flow underneath. Keep the heat low to prevent browning.
When the surface is mostly set but still slightly shiny and jiggles gently in the center, sprinkle with chopped herbs or cheese if you like. Cover the skillet briefly for about 30 seconds to finish cooking.
Remove the omelette from the heat once it has a pale, smooth surface with no raw whites visible. Let it rest in the pan for 1 minute to help it settle and retain moisture.
Gently slide the omelette onto a plate, folding it in half if desired. Garnish with additional herbs or a dash of hot sauce for extra flavor, and serve immediately.
