Chunk of Drake Flesh

Chunk of Drake Flesh can be found outside of the East exit of The Astralarium in the swamp area of Plains of Jarin, as well as in Issnur Isles east of Beknur Harbor. They are dropped by Irontooth Drake.

You can exchange one of those for a Drake Kabob by talking to the Collector Chef Lonbahn at Kamadan, Jewel of Istan.

Note
This seems to be a significantly rare drop.