Stainless steel breakfast bar support

Of course, you can first install a steel plate under the countertop and that should be enough to support the 15" overhang

Addressed this issue with a granite overhang in a previous apartment. Should say my cabinet makers did - let me see if I can recreate their solution.

They installed a wood (plywood?) insert flush with the base cabinet tops to support the granite - which they would have done w/w.o. the overhang issue. On the overhang side, the insert extended about 11" beyond the cabinet. That side of the cabinets needed to first be notched down to accommodate the one piece insert. It was then finished to match the cabinets; once the granite was laid on top, you couldn't even see the support, and there were no corbels in the way.

Clear as mud?

Another question if I may - Is there a way to smooth out the sharp corners of the SS breakfast bar?

I do not remember the name of the place but if you go to Chrystie Street (it is a short block) there is a great stainless stell place that probably take care of it for you. It is right after the glass place. If i remmeber the name or pass by I will post it