I like Ryan Farr's gourmet chicharrones, but I like the old-school stuff too.
Best I've had recently were from La Tapatia Market in Vallejo. I think they had a choice of three kinds, made in-house, sitting on top of the meat counter.
I'd sure love to find a source for those microwaveable ones they have in Mexico. They look like microwave popcorn.
La Tapatia Market
601 Broadway St, Vallejo, CA 94590