Crack the eggs into a mixing bowl and whisk thoroughly until well combined and slightly frothy. Add the fish sauce or soy sauce and mix again to evenly incorporate.
Heat a non-stick skillet over medium-high heat and add the vegetable oil, swirling to coat the bottom evenly. Wait until the oil shimmers and is slightly hot to ensure a quick sizzle when eggs are added.
Pour the beaten eggs into the skillet, tilting to spread the mixture evenly across the surface. Let cook without disturbance for about 30 seconds until the edges start to set and turn golden brown.
Reduce heat to medium and gently shake the pan to release any sticking edges. Continue cooking for another 1-2 minutes until the surface is mostly set but still slightly runny in the center. Optionally, sprinkle chopped green onions or herbs over the top.
3 large eggs
Fold the omelet in half using a spatula or carefully flip one side over the other, then cook for an additional 30 seconds to ensure the inside is cooked through. The omelet should be golden and slightly puffed, with crispy edges and a tender interior.
Gently slide the omelet onto a plate, slice if desired, and serve immediately hot, garnished with additional herbs if preferred.
