Take a shoulder roast, a dozen cloves of garlic (crished), half dozen tablespoons of oregano, six dried guajillo peppers, two each oranges/limes/lemons sliced in quarters and put it in a pot that just barely holds all of it.  Add water with some salt and pepper until it reaches about halfway up the roast.  Then let it sit covered in a 200 degree oven for 6 hours.  
Let it cool and remove the roast from the pot, discard everything else.  Shred the meat.  Heat a cast iron skillet and toss handfuls of meat in with a little oil to crisp up the edges a little bit and serve in corn or flour tortillas with green peppers, onion, cilantro, sour cream, and guacamole.  
Aoudad carnitas.