In Portland there are several locations for Voodoo doughnuts, they have vegan as well as non-vegan doughnuts on offer and are open late into the evening. I stopped by here for the first time after midnight with a taxi waiting just so I could try them, they were worth it. They're soft and taste the most like regular doughnuts that I've had.
Mighty-O is bashed in Seattle and offers wonderful cake doughnuts that I have traveled by far too far to obtain. There was a Canadian Thanksgiving I shall not mention in which myself and a grandpa that did not want vegan doughnuts went all over Seattle to find these.