Some years back, I helped develop a menu made up of variations on the
croque monsieur for a place up here in Madison, IN, and while that place closed before we could implement the new menu, I'm working with an established restaurant here to help redesign their menu and completely revise their marketing; we'll be seeing some of those variations soon. So I've thought a lot about hot toasty bread and melted cheese over the years.
At home, our default grilled cheese is sourdough bread, two slices of Boar's Head baby swiss cheese and, in between the cheese,
Penzey's Sandwich Sprinkle. That's good as is with tomato soup, but sometimes we add thin slices of Roma tomatoes and, on occasion, thin sliced white onions, which makes it a meal in itself. It's not the traditional grilled cheese, but it's heavenly. Add some French onion soup and a glass of merlot, and life is good.