This quest is available after completing Secret of the White Lily. Speak with Ursandel in Old Gridania at X11-Y14. He will tell you to visit his old manor. Do so, and you will unlock access to Haukke Manor.
Visit out dedicated Haukke Manor page to see how to beat the dungeon.
After, return to Ursandel, then head to Western Thanalan and talk to Minfilia to complete the quest.