there's a steel plate directly below the granite countertop which allows the round end to cantilever out, and we also did a tapered panel that came out from the end of the cabinet to help support the steel plate. Yes, you do need to have some type of substructure and if possible - add a tapered leg just for the added insurance!

Where did you get a steel plate made up? Did it go under the entire granite bar, or just maybe a foot in, then spacers the rest of the way to keep the granite level? Thanks for the help!

And what size was the steel plate? Thanks again!