I was at a farmers market once and bought a transcendentally good Banh mi from a food truck. They've never returned to the farmers market and I've never seen them anywhere else.
I've been wanting to do one that's basically the same as what I outlined, but vegan. I was thinking maybe if I take portabello mushrooms I could slice them on a mandoline to get like really flat mushroom rounds, roast those, use the jus and bits that won't slice flat from the mushrooms to make a vegan gravy, and have like a "roast beef" banh mi