Preheat the oven to 325 degrees F.
To prepare the pork: combine sugar, salt, pepper, paprika, mesquite, cumin, and oregano in a bowl. Optional to trim fat from pork ( I did not). Rub the pork on both sides with mustard using your hands to cover most of the shoulder. Season with the dried spice mixture all over ensuring fully covered. Place pork in a large oven safe dish and toss in those 4 garlic cloves. Pour the orange juice into the dish from the side ensuring not to remove any of the rub or spice from the meat. Do the same with the broth. Cover with foil and Cook for 3 1/2 hours until tender.
Remove from the oven and shred the meat. It should easily come apart using your hands, if not return to the oven for 20-30 minutes. Keep the shredded meat in its juices and discard fat here. The fat should easily come apart and be noticeably visible.
For the burritos: generously layer some shredded pork in the centre, top with shredded cheese and roll tightly ensuring both ends are closed. Repeat until all the burritos are rolled.
Place the burritos seam side down into a large baking dish. Spoon the enchiladas sauce overtop each burrito and spread to cover the entire tortilla. Top with additional shredded cheese and bake at 375 for 20 minutes or until warmed through.
Serve warm with shredded lettuce, fresh pico, and chipotle aioli. Enjoy