- Melt butter in a pot then stir in flour.
- Continue stirring while gradually pouring milk.
- Season with nutmeg, salt and pepper.
- Continue stirring until sauce becomes smooth and thick
- Arrange 4 slices of the bread on a flat surface, place two slices of ham on top, spread a small amount of bechamel on top of the ham then top it with another slice of bread.
- Heat a cast iron skillet, grease it some melted butter then add the sandwich, browning one side. Turn on the other side then continue to brown this side.
- Transfer sandwiches in a baking sheet then pour the bechamel sauce on top of the sandwiches, finally top it with the Gruyere cheese. Place it in an oven on a grill or broil setting, then broil until top is golden brown.
- Remove from oven, place it on serving platters then top with poached eggs, season with salt and freshly ground black pepper then serve.