5 tablespoons (about 2 ounces) achiote seeds
1½ tablespoons dried oregano, preferably Mexican
1½ tablespoons whole black peppercorns
1¼ teaspoons whole cumin seeds
½ teaspoon whole cloves
1 stick (6 inches) cinnamon (Mexican canela preferred) coarsely smashed
1 head garlic, peeled and roughly chopped
1½ cups sour orange juice (see note)
3 bone-in pork shoulder (Boston butt) roasts (about 25 pounds total)
3 packages (1 pound each) banana leaves, defrosted
For the achiote marinade: Measure the achiote seeds and oregano into a spice grinder, adding the black pepper, cumin, cloves and cinnamon, and run the grinder until everything's as powdery as you can get it (you may need to work in batches).
In a blender, combine the ground mixture with 1 tablespoon salt, the garlic and sour orange juice (or lime juice plus orange juice). Blend until smooth.
Put the meat in a large bowl or large plastic food bag and add the marinade, turning the meat to coat it evenly. (Do this quickly with your hands to avoid the achiote staining your skin. Refrigerate several hours or overnight.
When ready to cook: Line a large roasting pan with two packages of banana leaves, with the leaves overlapping the sides. Pull the meat from the marinade and add it to the leaves, scooping marinade over the meat. Spread the remaining leaves on top and tuck to seal.
Lower pan into preheated pit, cover and seal tightly (see accompanying directions). Cook 5-6 hours.
To serve: Remove the top banana leaves. Tip the pan to accumulate the juices in one end and spoon off the fat. Pour off accumulated juices, if desired, into a sauce pan and boil to reduce and concentrate the flavors. Season with more salt if necessary and serve alongside the pork.
Shred the pork and transfer to a large serving bowl or set out your cochinita pibil with a large fork for guests to help themselves.
Cook's notes: Look for sour orange juice (naranja agria) in the Hispanic aisle of the grocery store. If unavailable use 1⅓ cups fresh lime juice plus ⅓ cup each fresh orange juice and fresh grapefruit juice.
For a charcoal grill: Set the pan on the grill grate and close the grill cover. Grill until the meat is thoroughly tender (work a fork in near the bone -- the meat should easily come free), usually about 4 hours. If your grill has a thermometer, aim to keep the temperature between 300 degrees and 350 degrees. To maintain an even temperature with charcoal, add more charcoal regularly (usually a few pieces every half-hour or so). The pork can be baked in a 325 degree oven instead of on the grill; cover the meat rather loosely with foil before baking.
Adapted from recipes by chefs Rick Bayless and David Sterling