Melt the butter on low heat and brush one side of each slice of bread with some of it. Grill under a medium hot grill until golden. To make your Mornay sauce, to the remaining butter add the flour and cook for about 1 minute or so. Slowly add the milk continuing stirring until a thick cream. Add some of the cheese and the Dijon mustard and set aside.

To assemble your toast: on one of the slices of bread, start by layering some of the sauce, you ham and the chees and grill until melted. once golden, top with your other slice, and repeat by adding the sauce and the cheese and grill. Top with the fried egg and garnish with fresh herbs.