Kuby's Sausage House is pretty much as authentic as German food in Dallas can get; it traces its Teutonic roots back to Kaiserslautern in 1728, and serves up some of the best brats in the city.
Bavarian Grill is an authentic German schnitzel temple in Dallas that puts on an entire month-long festival dedicated to the beloved foodstuff, and's got a huge beer selection to BOOT. HA! German humor.
Edelweiss German Restaurant in Fort Worth isn't just serving up awesome German eats -- it's also emulating the Bavarian experience by putting on live performances by accordionists nightly.