Like those above, if I'm just holding for a few hours, my preferred method is to wrap in a couple of layers of foil, then wrap a towel or an old sweatshirt around that, then tuck the bundle into a small dry ice chest. I've held them for hours this way.
Caveat - if you take your brisket off the cooker and you're pleased with the texture and level of doneness, place the brisket on the foil but let it sit open for 20 minutes or so to let the temp come down just a bit before wrapping it up tightly. Otherwise it's going to keep cooking. If you take it off a bit before you think it's actually done to your liking, you can use that residual heat to finish cooking.
If it's going to be more than four or five hours before you eat, and the brisket is nicely done for your tastes, let it rest for an hour or so, then seal it up in a vacuum sealer bag with a little beef broth, and toss it down into a ice and water slurry until about 45 minutes before you want to eat. 45 minutes before eating, fill a big pot with enough water to cover the vacuum-sealed brisket. Don't open the bag. Set the pot and bag on the range and bring the water up to a simmer (NOT a full boil), and leave it in the simmering water for 20 - 30 minutes, or until juices are moving around and the brisket is hot. When it's nice and hot, you can turn off the burner and let the bag sit in the hot water to stay warm if necessary. Remove the brisket from the bag onto a cutting board, saving the juices (defatting if you time); slice as desired, and pour the juices back over the slices.
That's what I do, anyway.
Keri C
