We begin by preparing the sauce. Take a non stick pan, add some butter and let it melt. Add in the flour and roast, do not let it become brown.
Gradually add in the milk to get a thick soup, let it simmer, add in the parmesan cheese and bay leaf, allow it to come to a boil. Turn off the heat and keep aside.
Arrange the bread and add on the ham slices. Now take some more cheese (I took mozarella) and mix it with the sauce and spread on the ham. Cover with the other slice of bread.
You can add salt and pepper as per choice. Heat a pan, add in the rest of the butter. Place the sandwich in it for 2 minutes on simmer, turn and roast on the other side.
When both sides are nicely browned, remove it from the pan and place it on a serving plate. Pour the rest of the sauce on top of it and make sure you remove the bay leaf.
In the same pan, crack an egg and let it fry. Meanwhile place the sandwich in an oven till the top turns brown. Season the egg with salt n d pepper.
Just before serving, place the egg on the top, garnish with fresh thyme and serve hot.