Barbecued Chicken Sandwiches

2 broiler/fryer chicken (3 to 3-1/2 pounds each), cooked and shredded
1 large onion, chopped
2 cups water
1-1/4 cups ketchup
1/4 cup packed brown sugar
1/4 cup Worcestershire sauce
1/4 cup red wine vinegar
1 teaspoon each salt, celery seed and chili powder
1/4 teaspoon hot pepper sauce
Hamburger buns

In a 3-qt. slow cooker or Dutch oven, combine all ingredients except buns. Cover and cook on low for 6-8 hours in the slow cooker or simmer for 1-1/2 hours on the stovetop. Serve on buns. Makes 8-10 servings.

Note: 6 cups diced cooked chicken may be used instead of the shredded chicken.