To make the crepes:Mix milk, eggs, flour, and melted butter until smooth. Cook batter in a pan for 30 seconds, or until lightly golden. Do repeatedly until batter is finished.
Bechamel: Cook roux by mixing flour in melted butter in a saucepan over medium heat. Then gradually add milk and whisk until thick. Season with salt and pepper.
Scoop 2 tbsp. of chicken mixture into the center of each crepe and roll up. Then transfer to baking dish and pour bechamel sauce. Sprinkle remaining cheese.