Jameson Single Pot Still - Five Oak Cask Release is very much one of those whiskeys that does what it says on the tin. It's a pot still Irish whiskey, made from a grain recipe (or mash bill for our American friends) of malted and unmalted barley, which is triple distilled and then matured in five different barrel types. This includes bourbon and sherry casks, as well as three types of virgin oak, made from Irish, European, and American oak.