There is a pepper which is identified in all the books and other reference I can find as the Poblano - nice dark-green thing, heart-shaped and shiny, about 4-6" long. It's fairly hot when raw, more so than your typical Anaheim, but mellows to just barely spicy when cooked and has a great flavor. The other thing I like about it is the skin's so thin you don't have to peel it. As Mrs. O despises sweet peppers but loves the hot ones, I have been using these in any recipe calling for bell pepper, with excellent results.
Only thing is, in the regular commercial grocery and produce markets these are labelled "Pasillas." This despite the fact that a real pasilla is a long skinny dried pepper, as ALL THE BOOKS will tell you. It's as though we woke up one morning and suddenly cucumbers were being sold under the name of Banana, and no matter what evidence there was to the contrary they'd be labelled that way, they'd scan that way, and if you wanted your grocer to stock cucumbers you'd have to ask him to order bananas.
Perhaps this is a silly thing for an elderly man to be fussing about, but I just can't understand how a vegetable can get mislabelled in the first place, and then how that mislabelling can take on the quality of settled fact without anyone's hollering, "Hold it there, bud!"