I have to give 5 stars on this one.
I've been eating Edgar's tacos since they first started and it's crazy how consistent they are.
I don't know what classifies "authentic" Mexican tacos, but they literally only sell tacos (and a burrito I think) and English is not the first language of anyone here, which for me are always the required components of "authentic" anything.
This place is the Standard for tacos in Pittsburgh.
Get'em all... but I'm partial to the lamb and beef tongue.