Heat a dutch oven or heavy-bottom pot over medium-high heat. Once hot, add 1 1/2 tbsp of olive oil and half the pork. Brown the pork on all sides about 7-9 minutes, transfer to a plate. Add another 1 1/2 tbsp of oil and brown the remainder of the pork, transfer to the plate with the rest of the browned pork.
Reduce heat to medium and add 2 tbsp of oil. Then add the onion, salt, cumin, oregano and white pepper. Saute until fragrant about 1-2 minutes. Add the flour and stir until it starts to turn brown, about 1-2 minutes. Finally, add in green chiles, water, and pork. Stir well to combine. Bring to a boil, reduce heat to low, cover and let simmer for 1 hour or until the pork is fork tender.