Toss the stew meat with the flour until fully coated. Heat the oil in a large Dutch oven over medium heat until it shimmers; add the stew meat and cook, stirring from time to time, until meat is browned but not fully cooked. Add a little water to deglaze the pan, scraping up any browned bits. Add the onions, salt and pepper and cover with water. Bring to a boil and simmer, partly covered, for 90 minutes or until meat shreds easily with a fork. Add remaining ingredients, adding more water if necessary to cover, bring back to a boil, and simmer until vegetables are very soft. Adjust seasonings, and serve at once.