Sommelier Cup - William Adams

The mark on this says W A then E.P.O.C - which I discovered means Electroplate over Copper. It also says Hand Chased "1092" Made in England. Can someone please tell me the purpose of this dish? Were sugar cubes placed in here? It's too shallow to be a cup, and with the thumb handle, it has to have a specific purpose. Inherited from my grandmother.

Follow up:

Thanks for identifying!