Bake 20 minutes. Prick each brat three times with a fork, then turn over and prick the other side 3 times as well. Stir the veggies to ensure they aren't sticking to the baking sheet. Bake an additional 15-20 minutes or until the brats reach 160° internally and the potatoes are fully cooked. Sprinkle with parmesan cheese while allowing the brats to rest 5 minutes.