Don't waste any of your Christmas dinner, Make this Croque Monsieur instead!
Super easy left over sarnie....All you have to do is construct it as its all already made! Toast 1 side of the bread, remove from the grill and cover the other side with grated Parmesan, lay the ham on top then the sliced cheese and grill until melted.
Warm up the bread sauce in a pan and loosen with the milk. Put the second slice of bread on top of the melted cheesy one and cover with the hot bread sauce, cover with another layer of Parmesan and slap under a hot grill until lovely and bubbly! serve and don't burn your chin!