Ashes, Ashes pretty much summed up everything I would say (esp. about good, fresh, unfried corn tortillas), but I’ll add one more thing. As per shredded beef goes, you can simmer it in some enchilada sauce to help flavor and tenderize it. Throw it all in a crock pot, or a heavy stock pot or dutch oven over low heat. Or use green enchilda sauce and chicken. It’ll be falling apart and you can make a salad, or tacos, or even (gasp!) enchiladas ;).
You can have low fat refrieds but I consider it a sin (when I’m cooking anyways). I still make mine with lard, the way Og intended, and then regret it later when I hit the weights.