In a medium bowl mix together the olive oil, cumin, oregano, garlic powder, cayenne pepper, black pepper, lime juice, and salt. Rub the mixture onto the pork roast.
Place the pork roast in a baking dish and pour the orange juice, water, and vinegar around the roast. Cover the baking dish with aluminum foil and bake in preheated oven for 2 hours.
Uncover and continue baking for an additional 20 minutes. Remove from oven and let rest for 10 minutes before slicing.
Interesting Facts
Puerto Rican pork roast is commonly called "pernil".
The cumin, oregano, garlic powder, cayenne pepper, and black pepper combine to create the unique flavor of Puerto Rican cuisine.
Puerto Rican pork is often served with rice and beans.