Warning: This sandwich can be addictive! lol ...seriously though, i came up with this sandwich after watching the food network all day and scrounging through my fridge and pantry to see what i could come up with...and yes, i became addicted to the combination of flavors for quite a few months. =^.~=
Turn on broiler (can also be done in a non-stick frying pan, no need to use spray oil).
Butter one side of each slice of bread. Sprinkle parmesan on and spread around to cover butter completely. If using french roll, apply to inside.
Place in broiler or upside down in pan (on medium high). Brown cheese so it becomes as evenly brown and toasted as possible, but not black. Take care to watch it closely, once it starts to toast it can burn quickly. Remove to plate with non toasted side up for 10-15 seconds so it won't get steamed and soggy.
Turn over and lightly drizzle italian dressing over toasted side. Dip tip of knife in mayonnaise (about 1/4-1/2 tsp) and spread into dressing. It will mix as you continue to spread. Add additional mayonnaise if needed to be able to cover surface.
Lay 3 slices black forest ham on one side. Add optional items if desired.
Cover with other side, so that untoasted sides are out, and cut diagonally.
Hint - If using cheese, add to one side before drizzling dressing. Microwave for 20 seconds. Put dressing and mayonnaise on other slice only. Can also mix 1/4 cup italian dressing and 1/4 cup mayonnaise to use instead of mixing on the bread...if any is left, it won't go to waste...can be used to make another sandwich, or on a salad.