I don’t have a reliable source for you (I am searching, too), but these earlier discussions might offer some suggestions (the second link may not seem to be about pita, but is, and subsequent posts in that thread do have pita information):
Have you tried Saloniki in Cambridge? I’ve been a couple of times and the pita has always been freshly griddled and warm. It is a smallish pocketless pita. I can’t remember if Gre.Co in Boston does, but it’s a similar concept to Saloniki and I believe the pita is really fresh.
I’d recommended Crema Cafe up thread, but I must withdraw that recommendation. Their freshly made sandwiches have been poorly constructed of late, with fillings that fall out as you eat, and their premade sandwiches on pretzel bread have been soggy, and in the case of one tuna sandwich, off. (I complained and the person I spoke to said cheerfully, “oh yes, we try to serve fresh ones but sometimes you might get a left over one from the previous day.”)
Two visits to the Chik Chak truck at the Sci…