Cook beef and onion in a large Dutch oven over medium-high heat 10 to 12 minutes, stirring until beef crumbles and is no longer pink.
Drain, and return beef mixture to Dutch oven.
Add chili powder, salt and pepper.
Cook 2 minutes, stirring to toast chili powder.
Stir in chipotle peppers, tomatoes, tomato sauce, ketchup and water.
Bring to a boil, reduce heat.
Cover and simmer one hour.
Add beans 10 minutes before serving.
Garnish with grated cheese and green onions.