Saute onions in oil on medium-high heat until seared in a large, tall sauce pot.
Season necks with onion powder,salt, and sear on all sides over medium-high heat until the meat is uniformly golden dark brown all over (about 10-15 minutes.) Do not burn.
Add habaneros, fish sauce, paprika and onion powder. Fill with water until necks are completely submerged.
Boil then drop heat down to a low simmer. Simmer for 2-3 hours until meat is tender. Add water as needed. In a slow cooker this may take 4-5 hours.
When tender remove necks and allow to sit at room temperature until cool to the touch. With a fork scrape off the meat.
Reduce braising liquid until syrupy and add to shredded meat. Add only enough to flavor.
Serving
Serve on pasta, tortillas or as sandwiches with your favorite garnish.
Notes
Serve the finished, pulled lamb neck anywhere you would shredded meat like pulled pork.