If dry brining pork ahead of time, combine the salt and brown sugar and coat the outside of the pork shoulder. Cover in plastic wrap and refrigerate overnight or for at least 8 hours.
When ready to cook, remove pork from plastic wrap and brush off any excess salt & sugar.
Heat 2-3 tbsp of neutral oil in a large Dutch oven and sear each side of the pork shoulder until brown, about 3-5 minutes each side.
Remove from heat and add onion, soy sauce, fish sauce, ginger and garlic to pot. Pour coconut water over the pork shoulder.
Cover the pot and place in a 350 degree oven, and cook for 2.5 hours.
Remove lid and add in butternut squash. Cover and place back in the oven, cooking for another 30-40 minutes, until butternut squash is fork tender and pork is easy to pull apart. Internal temperature should be about 190 degrees.
Strain butternut squash from the pot and set aside on a serving dish. Remove pork and allow to cool till enough so you can handle it. Shred the pork and toss with the butternut squash. Drizzle some of the braising liquid on top for added flavor.
Serve over Jasmine rice, rice noodles or lettuce, and garnish with cilantro, limes and chili flakes.