Bernie Heisten
[59.39, 14.86]is a level 45 food and drink vendor located in Nethergarde Keep in the contested territory of Blasted Lands.
He is also the only source for the [Nethergarde Bitter], which is needed for the quest:
[62] Gaining Mirren's Trust.
Located inside of the castle in the Keep. Go north into the entrance, then turn west, and south into the side room.
See List of Blasted Lands NPCs.