Colorful Chicken Stew

1 pound boneless skinless chicken breasts, cooked and cubed
1 can (14-1/2 ounces) Italian diced tomatoes , undrained
2 medium potatoes, peeled and cut into 1/2" cubes
5 medium carrots, chopped
3 celery ribs, chopped
1 large onion, chopped
1 medium green pepper, chopped
2 cans (4 oz. each) mushroom stems and pieces, drained
2 chicken bouillon cubes
2 tsp. sugar
1 tsp. chili powder
1/4 tsp. pepper
1 tablespoon cornstarch
2 cups cold water

In a 5-qt. slow cooker, combine the first 12 ingredients.

In a small bowl, combine the cornstarch and water until smooth.

Stir into chicken mixture.

Cover and cook on low for 8-10 hours or until veggies are tender.