This quest is not available in game.
Use the Square of Imbued Netherweave while standing in Cenarion Refuge's moonwell to create a Sample of Primal Mooncloth. Bring the completed sample back to Nasmara Moonsong in Shattrath's Lower City.
*WARNING!* You can only select one tailoring specialization.
I can teach you the ways of mooncloth tailoring, if you are interested.. By specializing in mooncloth tailoring, creating primal mooncloth will yield twice the normal amount and you will have access to several exclusive patterns. All that is required is that you pass a simple test.
As to the test, your task is to create a small sample of primal mooncloth in the moonwell at Cenarion Refuge. I will provide all the materials you'll need. When you've created the sample, bring it back to me for examination.