I did a small search for this and didn't find but feel free to guide me to the answer.
I have a strong preference for whole beans with Mexican food. Black beans are my fave but pintos are great also. Refried are just not for me. Is there a reason that the majority of Mexican restaurants, in my experience anyway, serve one or the other? Is one from a certain region? And I'm not talking chains. We have a little joint near us with just a few stools, mostly takeout, totally authentic (they make and sell their own chorizo in the back) and they're refried only. Any guidance on this?