Food Network has a simple and easy-to-follow recipe for Puerto Rican pernil flavored with orange juice, vinegar and various seasonings. The recipe makes eight servings.
To make Food Network's recipe, combine 1/4 cup orange juice with 2 teaspoons white vinegar, 3 tablespoons olive oil and 10 minced garlic cloves. Also add 1 teaspoon cayenne pepper, 1 teaspoon dried oregano, 1 teaspoon ground cumin, 1 teaspoon ancho chili powder, 1/2 teaspoon freshly cracked black pepper and 1 teaspoon salt.
Wash and pat dry an 8- to 9-pound picnic-cut, bone-in pork shoulder. Place the shoulder fat side up on a flat surface and remove the fat. Using a knife, poke 1-inch deep holes into the meat and rub the spice mixture into the pork shoulder. Replace the fat and score it with diagonal cuts. Sprinkle with 1/2 teaspoon salt and wrap the meat with plastic wrap. Refrigerate for eight hours.
Remove the meat from the refrigerator one hour before cooking and preheat the oven to 400 degrees F. Pour 1 3/4 cups orange juice into a roasting pan and place the unwrapped meat into the pan. Roast for 30 minutes and lower the temperature to 300 degrees F. Cook for 3 hours 45 minutes, or until the internal temperature is 185 degrees F. Let the meat rest for 20 minutes, loosely covered, before serving.