Slow Cooker Italian Beef Stew

1 teaspoon beef base

3 large carrots, cut into 1-inch pieces (2 cups)

2 medium stalks celery, cut into 1-inch pieces (1 1/2 cups)

2 cloves garlic, finely chopped

1 medium onion, coarsely chopped (1 1/2 cups)

1/4 teaspoon pepper

1 can (19 ounces) Progresso® cannellini (white kidney) beans, rinsed and drained

1 can (28 ounces) crushed tomatoes in puree, undrained

1 jar (12 ounces) beef gravy

2 teaspoons Italian seasoning

1 teaspoon sugar

2 cups Green giant® frozen cut green beans (from 1-pound bag)