You'll have to look hard to find Hobo's Cafe next door to Amy Slate's Amoray Dive Center. But, this unassuming little hole in the wall serves the best grub food on Key Largo. Not gourmet, but substantial, good portions and tasty. Served in an Old Florida atmosphere with basic pub/bar furnishings.
The staff can get overwhelmed and it's not a place for a quick lunch. Just be patient, it's worth the wait. Dinner might be a better deal.