Coat pork with flour; shake off any excess. Heat oil in a large non-stick saucepan over medium-high heat. Working in batches, add pork and brown on all sides, about 5 minutes per batch. Transfer pork to a plate as it browns.
Lower heat to medium. Add the onion, capsicum, chopped chilli and garlic. Cook until onion is softened, about 5 minutes. Return pork to pan. Add the tomatoes, stock, chilli powder and salt. Simmer 1 hour, stirring occasionally. Stir in beans. Simmer until meat is tender and sauce is thickened, about 40 minutes.