Turn slow cooker on to high, put chicken in slow cooker with enough water to completely cover the chicken, chop onion and toss it into the slow cooker with the chicken.

Mix in ½ of the bottle of barbecue sauce, grape jelly, brown sugar, and Worcestershire sauce.

Cover and allow to cook on high for 3 to 4 hours, then turn down to low and boil out any extra water.

While water is boiling out, grab a fork and use it to shred chicken.  It should fall apart relatively easily.

Once the chicken is shredded, add the rest of the barbecue sauce and turn the slow cooker to warm.

Salt and pepper to taste