- Wash the pork shoulder.
- Skin side down, use a sharp knife to make incisions in different places of the pork shoulder.
- Grind together the garlic, pepper, oregano, and salt
- When done grinding, mix in oil and vinegar.
- Fill the incisions of the pork with the ground mixture. Whatever is left over rub on the outside of the pork.
- Put away in the refrigerator for 3 days. If you planned to cook it the same day, prepare the pork at least 1 hour ahead of time.
- Remove the pork shoulder from the refrigerator 2 hours before putting it in the oven.
- Preheat the oven at 350ºF (180°C) for at least 10 minutes before you begin cooking the pork shoulder.
- Cook the pork for 3½ hours.
- Raise the temperature to 375°F (195°C) and cook for 15–30 minutes until the skin is toasted and browned.