This quest/content can be acquired by playing a facebook game Dragon Age Legends. It will be automatically unlocked at the beginning of The Destruction of Lothering quest although its only possible to complete this in Act 1 onward.

To complete this quest during Act 1, you have to go to your Uncle Gamlen's Home in Lowtown  and enter the southern room. During Act 2 and 3 you can find it in the northern room in Hawkes Estate in Hightown. From there you can find inside a chest marked as Special Deliveries a belt named Evra's Trophy Belt. Upon taking the item, you'll complete this quest and received a codex entry Evra's Trophy Belt.