It is, quite literally, an eatable chocolate chip cookie shot glass filled with milk.
Chef Dominique Ansel Discusses His Latest Mouthwatering Creation, the Milk & Cookie Shot, at SXSW|Marlow Stern|March 10, 2014|DAILY BEAST
In familiar language, the term is applied to any product of a plant containing the seed, more especially those that are eatable.
Cooley's Cyclopdia of Practical Receipts and Collateral Information in the Arts, Manufactures, Professions, and Trades..., Sixth Edition, Volume I|Arnold Cooley
Being prepared in a civilized fashion, I suppose, the officers found them eatable.
The Log of a Sea-Waif|Frank T. Bullen
How they can use me I can't imagine, as I am not eatable, and they do not need fires, yet without me they can not live.
Harper's Young People, March 22, 1881|Various
He ate like a dog whatever he could get that was eatable, without particularly thinking of what it consisted.
Pelle the Conqueror, Complete|Martin Anderson Nexo
The adjective force of the infinitive comes out clearly in nothing to eat, where to eat is practically synonymous with eatable.
An Advanced English Grammar with Exercises|George Lyman Kittredge