The tacos at Fuel City are as good as they're reputed to be. I recommend the barbacoa, the pastor (picante!) and picadillo. Oh, and the tomatillo sauce.
Fuel City tacos, chicken fried rib-eye from Breadwinners and beef ribs from Pappas. Who doesn't love beef ribs from a BBQ pit with a cow on the roof.
Dallas has good food. Souvenir eating at it's finest.