Preheat the oven to 400°F
Pat the pork loin dry with paper towels
Trim excess fat if needed
Rub the pork loin with oil
Season all sides with salt, pepper, and desired spices
Place the pork loin in a roasting pan or oven-safe skillet
Insert a meat thermometer into the thickest part
Roast for 20 to 25 minutes per pound
Check for an internal temperature of 145°F
Remove the pork loin from the oven
Tent loosely with foil
Rest for 10 to 15 minutes
Slice and serve