In a mixing bowl, whisk together flour, eggs, milk, melted butter, and a pinch of salt to make the crepe batter.
Heat a frying pan over medium heat and pour a ladle of batter to make a thin crepe. Cook until golden on both sides. Repeat with remaining batter.
Preheat oven to 375°F (190°C).
In another bowl, beat egg yolks and mix in grated cheese, melted butter, and a pinch of salt.
In a separate bowl, beat egg whites until stiff peaks form. Gently fold into the cheese mixture.
Place a crepe in a baking dish, spread some souffle filling, and fold. Repeat with remaining crepes and filling.
Bake in preheated oven for 10-15 minutes until puffed and golden.