I broke several sous vide "rules" and produced a very successful first-cut brisket.
First, I seasoned that flat to the hilt, just as if I were going to braise it. I also included carrots, raw onions and beer in the cooking bag.

Second, I used the resulting liquid after the cook to make a fantastic sauce.

Third (not really a sous vide no-no but more of a personal no-no), I used a flat.

I did this because, as I posted upthread, I figured that it was a fairly useless and unforgiving cut and would therefore be a good cut to experiment with.
I used a 4.5-pound flat from Costco (went ultra-cheap in case of failure) and cooked it at 140 F for 48 hours. After the cook, I re-seasoned the brisket and cooked it at 375 F (convection roast) for 15 minutes to produce what turned out to be a delectable crust. I strained the leftover cooking liquid, brought it to a hard boil and then reduced it by about 2/3. I re-seasoned it at the very end and served it with the meat.
The result was a flavorful, very tender and moist brisket. The cooking method somewhat made up for the fact that it was a flat. It was not as good as a whole brisket or a point but for a flat it was damned nice and most importantly, I think it was better that what braising normally produces. I'd probably cut back a little on the onion next time but I definitely wouldn't omit it, as it imparted nice flavor into the meat and the sauce. With Passover just around the corner, I'm seriously considering putting this method in play for the holiday briskets.
=R=
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