You're a little confused there, pardner. Pasillas are fresh chiles, called chiles negros when dried. Anchos are dried chiles, called chiles poblanos when fresh. Now that we've got that straight, we still don't know whether you have anchos or poblanos. They're around the same medium level of hot, but have different flavor profiles. I'll try and stick to what works with both.
While I love mole poblana (the chocolate one) as much as or more than the next person, and even though both types of dried chile are necessary to it, I wouldn't casually recommend making it. It's time consuming and has an ingredient list as long as your arm. Worth it though.
Either kind of dried chile can be used to make a great ranchera (country style red sauce), by cleaning (getting rid of the seeds and veins), reconstituting in water, pureeing and cooking down with onions, tomatoes, etc., or reconstituting, adding to onions and tomatoes, cooking down with liquid, then pureeing. Good for enchiladas, rellenos, chicharrones, all sorts of good things. Just your basic ranchero
Great with beef. Clean, reconstitute, mince and use to flavor beef fillings for anything stuffed -- tamales, pasties, somosas, you name it. Or, reconstitute and puree, or just make powder and use it in regular old beef chili.
Excellent with lamb. Not bad with chicken either. Not the first choice for pork which prefers chilies on either side of the grassy/fruity spectrum -- or smoky like chipotles -- in other words, with a lot going on. Chiles negros and anchos are more in the versatile, conservative middle. They're even more versatile when mixed 50/50 with chipotle.
They do fusion, and will adds some depth to and mellow (by comparison) vindaloo and phal. Man, I love vindaloo.
Very good in barbecue and steak rubs. However much you use, compliment with an equal amount of sweet paprika and half the amount of ground cumin (of course you need the other rub ingredients like salt, black pepper, garlic powder, etc., also). Along with some granulated garlic, this is a good recipe for a basic "chili powder," too.
Clean very thoroughly (NO seeds, NO veins AT ALL), grind fine, and mix about 1/2 tsp per tbs of cocoa powder. Adds some zest to the late night comfort thing, along with a splash of brandy or rum and some vanilla. Makes for an interesting mousse, too.
BDL