HEAT a large saucepan over medium. Add oil, then onion and garlic. Sprinkle with chili powder, chipotle, oregano and salt. Stir occasionally until onion softens, about 3 min. Meanwhile, slice pork into bite-sized chunks. Add to onion mixture.
POUR in tomatoes. Using a wooden spoon, scrape up and stir in any brown bits from pan bottom. Bring to a boil, then reduce heat to medium-low. Cover and simmer, stirring occasionally, to develop flavour, 10 to 15 min. After chili has simmered 10 min, stir in peppers and beans. Cover and continue cooking until beans are warmed through, about 5 min. Remove from heat. Spoon into bowls.