Unless you have a pit in your yard, you can't cook this in the traditional way, which is to wrap the meat and marinade closely in banana leaves and slow cook it in a pib, an earth oven. But cooking your cochinita pibil in a regular oven is pretty close -- only you'll want to get as much smoke into the deal as possible. I find using smoked salt works well, and if you can get some, use it. If not, no biggie. The weird herbs in this recipe, the epazote and avocado leaves, are actually pretty easy to find in Mexican markets, and chances are there's one near you. If you can't find them, skip it.
2tablespoonsroom temperature lard or vegetable oil
2teaspoonssmoked salt(see above)
2to 4 pounds shoulder meat from pork,wild pig or javelina
1bunch fresh epazote, chopped(optional)
3avocado or bay leaves
Pickled red onions
Minced habaneros or rocoto(chile manzano)
1cupannatto (achiote) seeds
1/4cupdried Mexican oregano
1teaspoonwhole cumin seeds
1head of garlic, charred on a stovetop and peeled(see note below)
3/4cupbitter orange juice(see note below)
If you are making your own recado rojo, the achiote paste, grind the annatto seeds in a spice grinder. The seed are hard, to you will need to grind, sift into a bowl, then grind some more. When the seeds are ground into a powder, mix them with the vinegar and set aside. Incidentally, you can get powdered annatto, but unless it's bright red, don't buy it -- the flavor gets old and stale fast. Put the oregano, cumin seeds, peppercorns and allspice into the grinder and grind that into a powder. Add it to the bowl with the achiote. Move the spice mixture, the garlic and orange juice to a food processor or blender and process until you get a thick paste. This will keep in the fridge for months.
Get a heavy, lidded pot that will hold the meat snugly. You can either keep the meat on the bone if it will fit into the pot (javelina shoulders do), or cut it into pieces that will fit. If for some reason you are using hind legs, you will want to cut the meat across the grain into hunks about 2 to 3 inches across. If you don't do this, you will have very long strands of meat when you are ready to eat it, which isn't so nice. Mix the achiote paste with the lard, salt and enough bitter orange juice to make a sauce like a very thick BBQ sauce. Put the meat into the pot and pour the sauce over it. Massage the sauce into the meat as best you can (maybe wear gloves, as the annatto stains unless you wash your hands the second you're done), and, if you have time, Set everything into the fridge for up to a day. You don't have to do this, but a long marinade is traditional, and helpful if you cook at high-ish temperatures.
When you are ready to cook, take the meat out of the fridge and sprinkle the epazote and avocado leaves over it. Cover the pot and put it into a 250°F oven. If you do this, the meat will take between 6 and 8 hours to cook, but will be of better texture. If you are in a bit more of a hurry, set the oven to 300°F and the meat should be ready in 3 to 4 hours.
When the meat is ready to fall off the bone, shred it with two forks. With wild pigs or javelina, I like to add anywhere from 1/4 cup to 1/2 cup of lard to the mixture, to keep it from getting dry.
Serve on tortillas with pickled red onions and some minced habaneros. Drizzle a little extra lime or bitter orange juice on it when you serve your tortillas.
If you want to make your own achiote paste, you prep the garlic by essentially setting the head of garlic on a gas burner and letting it catch fire. Obviously run the stovetop fan on high while doing this. Use tongs to move the garlic around, so it all cooks reasonably well. Let it cool and peel. You'll have some blackened bits, and this is good. Just don't incinerate the whole thing.