best way to reheat pre-cooked brisket?

As a Restaurant chef, I preheat by portion size. Take some of the fat.... melt it in a little beef stock that I make into a very thin gravy with added mushrooms, onion, and garlic. Get that hot, then... put in sliced brisket... cover .... heat and serve. That'll be $5 please....LOL... just my humor thing. Really worth much more then that...hahahaha

We always skim off all the solidified fat, then slice it cold, Put into clean pan and cover with the sauce. Heat slowly like Monita said.

I always slice first. Very easy when it's cold. Cover with the sauce. Cover pan and re-heat in oven 250-300. Take out the brisket 30-40 min before you want to re-heat so it doesn't go into the oven ice cold

Highly recommend slicing it cold, then heating in the sauce - either stove top or in the oven. Covered.