Looking for a decadent tasting fat free hot sandwich recipe...

I rarely eat sandwiches post op because the fat free Greek yogurt /horseradish mustard dressing I use is BORING and without it ..

cold cuts and fat free melted American cheese just don?t get me excited.

I also rarely eat more than a bit of the bread ( which is always sourdough fresh and artisanal).

The argument for coming up with a delicious sandwich recipe is how convenient popular and lowfat cold cuts are . A ten minute great tasting healthy and hot sandwich would be a great addition to a repertoire of post bariatric healthy recipes.

So im thinking about incorporating very tasty veggies for the needed moisture like I do in my normal recipes -

Yesterday I experimented with a layer of leftover green bean casserole , lean roast beef and a bit of lean pastrami. ( with my usual Greek yogurt /mustard spread on the bread ) It was actually quite good and high protein, fat free and healthy except that the bread-spread was predictably boring.

Today i want to improve it in the direction of a Philly cheese steak... minus the fat of course . Ideas ?

What im really trying to come up with is something iconic and unforgettable tasting - like the Reuben/Big Mac used thousand island dressing and saurkraut or a fresh tomato slice as the vegetable ingredient and necessary moisture .