Prepare the Pork Shoulder:

Rinse the pork shoulder under cold water and pat it dry with paper towels. Place it on a cutting board and make several deep slits across the surface of the meat, about 1 inch apart. This helps the marinade penetrate deeply and ensures even cooking.

Make the Marinade:

In a blender or food processor, combine garlic cloves, dried oregano, ground cumin, black pepper, paprika, adobo seasoning, salt, olive oil, orange juice, lime juice, white vinegar, and bay leaves. Blend until you achieve a smooth, fragrant marinade.

Marinate the Pork:

Place the pork shoulder in a large, shallow dish or a resealable plastic bag. Pour the marinade over the pork, making sure to coat it thoroughly, including inside the slits. Massage the marinade into the meat, cover the dish or seal the bag, and refrigerate overnight for best results. Allow the flavors to meld and infuse into the meat.

Preheat the Oven:

Preheat your oven to 325°F (160°C). Remove the marinated pork shoulder from the refrigerator and let it sit at room temperature for about 30 minutes to take the chill off.

Prepare the Roasting Pan:

In a roasting pan, arrange the thinly sliced onions and bell peppers to create a bed for the pork shoulder. Drizzle with olive oil and season with salt and pepper to taste. Place the marinated pork shoulder on top of the bed of onions and bell peppers.

Roast the Pernil:

Pour orange juice and chicken or pork broth over the pork shoulder and vegetables in the roasting pan. Cover the pan tightly with aluminum foil, ensuring a snug seal to lock in moisture.

Place the roasting pan in the preheated oven and roast the pernil for approximately 4 to 5 hours, or until the internal temperature reaches at least 190°F (88°C). For a crispy skin, uncover the pork during the last hour of cooking, basting occasionally with pan juices.

Rest and Serve:

Once the pernil is cooked to perfection, remove it from the oven and let it rest, covered loosely with foil, for about 20 to 30 minutes. This allows the juices to redistribute, ensuring a moist and tender roast.

Carve the pernil into thick slices, serving alongside the roasted onions and bell peppers. Spoon any remaining pan juices over the sliced meat for added flavor and moisture.

Serve the Puerto Rican pernil hot, accompanied by traditional side dishes such as arroz con gandules (rice with pigeon peas), tostones (fried plantains), or yuca con mojo (yucca with garlic sauce).