Preheat the oven to 180°C (356°F).

Heat 150 ml milk until hot but not boiling.

Whisk 2 egg yolks with 25 g wheat flour in a mixing bowl until smooth.

Whisk half of the hot milk into the yolk mixture.

Whisk in the remaining hot milk until the batter is fully combined.

Melt 20 g butter in the oven-safe frying pan over medium heat.

Reserve a thin coating of melted butter in the frying pan for greasing.

Whisk the remaining melted butter into the yolk and milk mixture.

Season the mixture with salt and black pepper.

Cook the yolk mixture over medium heat for 1 minute while whisking continuously.

Whisk until the mixture thickens into a smooth béchamel-like base.

Remove the thickened base from the heat and whisk briefly to cool it slightly.

Whisk 4 egg whites with a pinch of salt in a clean mixing bowl until stiff peaks form.

Whisk half of the whipped egg whites into the warm base to loosen it.

Fold the remaining whipped egg whites into the mixture gently with a silicone spatula.

Fold 15 g Comté cheese into the soufflé mixture.

Season the mixture with black pepper and ground nutmeg.

Ensure the oven-safe frying pan is evenly buttered with the reserved butter.

Pour the soufflé mixture into the buttered oven-safe frying pan.

Cook the omelette over medium heat for 1 minute to set the bottom.

Bake for 2 minutes at 180°C (356°F) until puffed and lightly set.

Invert the soufflé omelette onto a plate.

Serve immediately while the omelette is hot and airy.