Cattelack for the pastrami (really), pecan lodge for the brisket, Lockhart for the sausage, and hard eight for the experience. Smoke at the Hotel Belmont is the best brunch BBQ (brunch in Dallas is a sport).
If you have a weekend off...take an Uber to the Katy Trail Ice House in Uptown.
Dallas is an awesome city for a young professional, if you can escape the confines of the training hotel.