Heat the oil in a large pot over medium-high heat. Add the pork and 2 teaspoons of salt. Brown the pork on all sides, stirring regularly. Remove the pork from the pot and pour out all rendered fat, saving about 1 tablespoon.
Add the onions, remaining salt, cumin, coriander, and oregano to the pot. Sauté for 3-5 minutes. Then add the garlic and peppers. Sauté another 3-5 minutes. Add the chopped tomatillos, bay leaves, and cilantro. Toss the pork with the masa and add back to the pot. Stir well.
Finally add the water. Bring to a boil, then reduce the heat to low. Cover and simmer for 3 hours, or until the pork is falling apart, stirring occasionally.
Take 2 forks and break the pork up even more. Salt and pepper to taste.
Leftovers store well in an airtight container in the fridge for up to 3 days, or in the freezer for up to 3 months.