In 41⁄2- to 5-quart Dutch oven, heat oil over medium heat.
Add bell pepper, onion and garlic; cook 5 to 6 minutes, stirring frequently, until onion is softened.
Stir in remaining ingredients except polenta and green beans.
Heat to boiling.
Reduce heat to medium-low; cover and cook 35 to 40 minutes, stirring occasionally, until carrots are tender and stew is hot.
Meanwhile, cook polenta as directed on package; keep warm.
Stir frozen green beans into stew.
Cover; cook 5 to 6 minutes, stirring occasionally, until beans are hot.
To serve, spoon stew over polenta.
Notes & Wine Advice
Any type of canned beans, instead of the cannellini beans, will work in this recipe. You may want to experiment with garbanzo beans, butter beans, great northern beans, red beans or kidney beans.