The night before cooking, cut pork shoulder into 1 to 2-inch cubes.
Apply salt to pork and mix into the meat to coat evenly.
Put seasoned pork on a wire rack over a rimmed baking sheet and refrigerate overnight, uncovered.
The next day, preheat your oven to 325⁰F.
In a small sauce pan, toast whole cumin seeds, whole coriander seeds, and black peppercorns over medium-high heat for approximately 1-minute. Grind with a pestle and mortar, or a spice grinder and mix with chili powder and oregano. (Toasting whole seed seasonings is not completely necessary. Feel free to use pre-ground seasonings, just reduce the measurements by half).
Remove pork from fridge and apply rub, mixing and massaging into the meat until evenly coated.
Add meat, chicken broth, juice of two oranges, juice of two limes, quartered onion, garlic cloves, and bay leaves to a large, heavy-bottomed pot or Dutch oven. Bring to a boil.
Transfer to oven and braise, partially covered for 2 ½ hours, stirring occasionally until tender.
Remove from the oven and discard the bay leaves.
Optional Rest:
Optionally, reduce heat to 160 - 170⁰F and keep pork warm until ready to serve. Temperature can be held for several hours (recommended) up to overnight.
Street Taco Assembly:
Either directly after braising, or resting overnight, preheat a large cast iron skillet or griddle over medium-high heat. Fry pork in batches until edges are crisp but still tender in spots, approximately 5 - 8 minutes per batch.
Place fried pork on tortillas and top with finely minced onions, cilantro, and lime juice.
Optional toppings include, hot sauce, salsas, pickled onions, jalapenos, Mexican crema, and cotija cheese, etc.