Cook the omelette for 1 to 2 minutes: The omelette will finish cooking in 1 to 2 minutes. When done, the bottom will be set and the edges will look crisp. The top of the omelette should still look fairly wet and uncooked, but there will no longer be any loose, easily flowing liquid egg — the omelette will continue cooking off the heat, so finish when you think the top still seems a bit underdone.