Preheat oven to 400°F (200°C).
Place the pork loin in a glass baking dish (ceramic or metal also works).
Drizzle with olive oil and fresh lime juice.
Season generously with garlic powder, cumin, sea salt, Italian seasoning, paprika, and black pepper.
Rub the spices into the meat. Flip the loin over and repeat seasoning on the other side.
Add half of a sweet onion, cut into chunks, around the pork loin in the baking dish.
Bake for about 20 minutes per pound (for a 3.5 lb loin, about 70 minutes), or until internal temperature reaches 145°F (63°C).
Remove from the oven and let rest for 10 minutes before slicing.
Serve and enjoy!