Since vegan food wasn't a particular gem of Greenland, we stocked up in a supermarket and cooked out own food. You can buy some gas in an electronic store in town (60 dkr). In addition, there were still a couple of places with vegan food: Kangji coffee shop (wi-fi, decent vegan options), Inuit restaurant, Marmaut, hotel Icefijord (fancy!), Hong Kong restaurant (veggie curry)