Croque monsieur with Le Gruyère AOP

Begin by making a thick béchamel sauce. Melt the butter in a saucepan and stir in the flour. Cook and stir for a minute or so to cook out the floury taste, then stir in the milk bit by bit, ensuring any lumps are whisked out before adding more milk

Once all the milk has been added and you have a smooth, thick sauce, stir in the Dijon mustard then taste and add nutmeg and salt until you're happy with the flavour. Remove from the heat and set aside

Make the Dijon mustard by stirring the mustard and mayonnaise together. Set aside

Now it is time to assemble the sandwiches. Begin with a layer of Dijon mayonnaise, followed by a slice of ham and then slices of Gruyère cheese. Close the sandwich and spread the top of the lid with some béchamel sauce

Place the sandwiches on a tray and under the grill for a few minutes until the béchamel has started to colour and the cheese is nice and melted

Serve immediately with an extra dab of Dijon mayonnaise on the side