This is a great way to use up leftover roast beef, flank steak, whatever you have around. If you plan ahead, save some gravy for this. You could even throw some chopped meat and gravy in the freezer and make this much later. I didn’t have leftover gravy but mixed up some of the “instant” gravy from a dry mix.
Edited to add: I don’t like using those packets so later learned a way to make a quick gravy.0