A buddy of mine down in Springfield who has a Barbecue stand not too far from the Cozy Dog, is thinking about adding Italian Beef to his menu. We were passing through town this past Christmas on our way to Kansas City, so I brought him some deconstructed samples of Al's Italian Beef, including the sliced beef itself, bread, sweet and hot peppers, and of course, a couple of pint tubs of au jus. He took one taste of the au jus and declared, "Dang, there's tarragon in here!"
I found it odd that of all the potential herbs and or spices that one could find predominant in Italian Beef juice, that tarragon, a spice I'll bet not many round these parts would immediately associate with said gravy, would stand out. Sure enough though, when I tasted a spoonful, there it was, plain as day; a distinct hit of tarragon that really added a nice complexity and a bit of mellowness to the flavor.
So that's my thought for the day. Hope it was helpful.
Buddy