Preheat the oven to 325 degrees F.
the skin of the pork shoulder
. Put it into a large bowl or baking dish
and pour in 3/4 of the marinade, making sure to coat the entire piece of pork. Cover and refrigerate for at least 30 minutes or up to 2 hours.
Put the pork shoulder, skin side up, in a roasting pan fitted with a rack, Cover with foil and roast
in the oven for 3 hours. After 3 hours remove the foil, turn the heat up to 425 degrees F and roast until the skin is brown and crispy, about 30 to 45 minutes. Make sure to check every 5 or 10 minutes to make sure the skin does not burn. Remove from oven to a cutting board and let rest for 10 minutes before carving. Carve the meat and arrange it on a serving platter. Pour the reserved marinade
over the carved meat just before serving.