I have not personally used banana, however I had read alot of stories as well as comments from people who have and it seems that using an actual banana yields the same results you had. However I have heard of many people using the baby food banana's w/alot of success.
Hair Type: A head full of THICK, normal porosity curls/coils that I am TOTALLY in LUV with!
(Transitioned for 16 & 1/2 months)

Loving: MC LI Condish, Raw shea butter, Coconut & Grapeseed Oil, SM raw shea butter shampoo,HEHH Conditioner, Braggs ACV & Egg, Mayo & EVOO PT's