What is the best solution for a banana roll deformity?

Physical examination is necessary to see whether the banana role as a product of surplus fat or buckling of the skin. If that is the issue this areas susceptible to treatment. Skin buckling could be corrected with excision along the gluteal fold the most of the time the trade-off is not worth it.

Some banana rolls can be treated with liposuction, and some may need to tighten excess skin. Some laser liposuction is helpful in tightening skin. What you need specifically can be determined during the consultation. I would suggest meeting with a board certified plastic surgeon and discussing all your concerns. You do not have to just live with it.