In large saucepan or Dutch oven, heat oil over high heat; brown beef in batches. Transfer to plate.
Add bacon to pan; cook over medium heat for 5 minutes or until crisp. Drain off fat. Add onions and garlic; cook, stirring occasionally, for 5 minutes or until softened.
Sprinkle with flour; cook, stirring, for 1 minute. Add stock and water; bring to boil. Reduce heat to medium-low. Return beef and any juices to pan; add tomato paste, thyme, salt and pepper. Cover and simmer, stirring occasionally, for 1 hour.
Add sweet potatoes and red and green peppers; cook, covered, for 30 minutes or until potatoes are tender. (Make-ahead: Let cool for 30 minutes; refrigerate in shallow airtight containers for up to 2 days. Reheat to continue.)