How do I remove powders since Fruma?

Seems like a really dumb question to ask, but I just havn't figured out how to do it yet. I know you can now add powders directly to the Items but I dont know how to remove them. The Fruma Update page only says Im getting a refund when I do remove them but how to do that isn't described on the page so heeeelllpppp!!!!! Pls.

 

Item upgrader npc in the same location as the powder master npc.