Preheat oven to 425 degrees and grease a sheet pan. Line half of the sheet pan with foil, folding up the sides about 2 inches from edge (to make a "tray" and prevent the pork juices from spilling out). Place the tenderloin in the center of the foil tray.
Pat the tenderloin dry with a paper towel. Whisk together garlic, brown sugar, soy sauce, red pepper flakes, balsamic vinegar, and paprika. Pour mixture over the pork tenderloin, then turn the tenderloin over a couple of times to make sure all sides are coated well.
Arrange the potatoes on the other half of the sheet pan (on the half with no foil). Drizzle with oil, and toss to coat, then season with salt and pepper to taste, Italian herbs, garlic powder, and Parmesan cheese.
Bake in preheated oven for approximately 20-25 minutes, using tongs to turn the pork over in the sauces every approximately 5-10 minutes. *You can even switch the oven to BROIL for the last 2-3 minutes to brown the pork and potatoes - but watch it carefully so it doesn't burn! Allow pork to rest for approximately 5 minutes before slicing into around 1-inch sections and serving.