In large skillet, cook ground turkey, onion and garlic until turkey is thoroughly cooked (8-10 min.). In large stockpot, combine all ingredients except beans. Bring to a boil; reduce heat to low. Simmer, covered, 1 hr. stirring occasionally. Stir in beans; continue cooking until heated through (about 15 min.). Top each serving with sour cream and shredded Cheddar cheese, if desired.