1 tablespoon water
2 eggs, the yolks separated from the whites
Pinch of salt and white pepper
1 tablespoon butter
2 tablespoons grated Cheddar or Cheshire or another flavorful cheese
herbs: 1 tablespoon finely chopped fresh parsley, chives, or dill
onion: 1 tablespoon chopped, sautéed in 1 teaspoon butter until soft and translucent
mushrooms: 2 tablespoons sliced, cooked in 1 teaspoon butter
1. Preheat broiler
2. Stir the water and the egg yolks vigorously until well combined. Stir in a pinch of salt and pepper.
3. Whisk the egg whites until stiff. Gently fold the egg whites into the yolks until just combined.
4. Over medium heat, melt the butter in an oven-proof omelette pan. Tip the pan from side to side to coat well with the butter. Pour in the egg mixture. As the edges set, lift them away from the sides of the pan and let the uncooked egg run under. When the bottom is well set, put the pan under the broiler and cool a minute or so to set the top.
5. Remove the pan from the broiler; spread filling over 1/2 of the omelette.
6. Run a spatula around the edge of the pan, fold the omelette in half, and slide out onto a warm plate. Serve piping hot.