Re:Grilled Cheese and Potato Sandwich
i've been putting mustard in between the slices of cheese since i was a teenager - long before good eats was around!
i usually mix in some good thinly sliced imported ham. or some turkey. or bacon & tomato or just one or the other. and i usually mix a few different types of cheese - mozz, cheddar, american - cooper sharp, provolone, cheddar - swiss, american, provolone.
my fav bread to use is rye although pumpernickel, sourdough or hallah are also good.