Find a deepore boulder to make a millstone. These are lighter colored rocks that look like mining nodes. (Several can be found around ( -353, -388, -711 ) /waypoint -353, -388, -711 and ( -637, 0, -551 ) /waypoint -637, 0, -551 east of the Ring War battlefield. Approximate ten minute respawn time).
When you inspect one a boiling blistercrag will spawn and attack you; kill the boiling blistercrag to update the quest. This may take several inspections (up to ten have been reported).