Place chicken in slow cooker. Combine next 3 ingredients; pour over chicken. Cover with lid.
Cook on LOW 8 to 10 hours (or on HIGH 5 hours).
Remove chicken to serving platter; cover to keep warm. Add sour cream to slow cooker; stir until well blended. Serve over chicken.
Serving Suggestion: Serve over hot steamed vegetables. Or, spoon over 2/3-cup servings of hot cooked brown rice.
Cooking Know-How: Heat releases the fragrant flavorful oils in curry. For optimum flavor, measure the curry powder into a small mocrowaveable bowl and microwave on HIGH for 30 seconds before adding to the slow cooker.