Pull out a large Dutch oven (alternatively a slow cooker or stockpot).
Put the pork belly into the pot.
Cover it with cool water.
Add salt and vinegar.
Soak for 20 minutes.
Drain thoroughly.
Rinse off salt.
Rinse out the pot.
Put the pork belly back in the pot.
Cover again with water.
Bring it to a boil for 2 minutes.
Drain the pork belly and rinse it.
Clean the pot once more.
Using a sharp knife, cut the pork into cubes measuring about 1.5”.
Create a paste by grinding shallots, garlic, and salt together.
Use the paste to coat the pork cubes as easily as possible.
Place in a bowl with tamari and pepper.
Marinate in the refrigerator for 1-2 hours.
Warm up the pot on medium heat. Add the sugar, watching it closely.
When it turns golden brown, add the oil and stir.
Turn the heat up to medium-high.
Brown the pork pieces in the sugar and oil (you want them brown on all sides).
Pour coconut water into the pan. Add the 5-spice, onion, chili, and the remaining pork marinade.
Bring to a boil, then reduce to low heat.
Simmer for 2 hours (top off).
Stir every 20 minutes, removing any foam from the surface.
Your stock should be reduced to ½ the original amount.
Remove the chili peppers and onions.
Check to see that your pork is tender. If not, let it simmer a little longer.
Taste test, adjusting the spices, tamari, or soy to personal preference.
Serve over rice.