Pork tenderloin is the cut of meat taken from the muscular area along the pig's spine. According to Bryan Miller, Marie Rama and Eve Adamson, authors of "Cooking Basics for Dummies," while pork tenderloin is already a succulent cut, slow roasting will infuse it with flavor and further tenderize the meat. Slow roasting pork tenderloins requires fewer than 10 minutes of preparation, and an hour or two of bake-time.
Preheat the oven to 450 degrees F.
Mix olive oil, ground sage, ground pepper and salt together in a small bowl with a spoon.
Place the pork tenderloin onto a clean working surface and rub the olive oil and seasoning mixture into the meat. Do not neglect any part of the roast, if you run out of the mixture, make a second batch to ensure the meat is coated thoroughly.
Place a V-shaped roasting rack into a roasting pan.
Place the seasoned pork tenderloin onto the roasting rack and set into the oven.
Reduce the oven's temperature to 250 degrees F and bake the pork tenderloin for 45 minutes per pound of meat.
Remove the roast from the oven and place onto a clean working surface.
Let the meat sit for 10 minutes before slicing and serving.