Place chicken breasts in a slow cooker.
In a mixing bowl, combine barbecue sauce, seasonings, apple cider vinegar, and liquid smoke.
Pour barbecue mixture over chicken breasts and brush to thoroughly coat.
Top chicken with pats of butter.
Cover slow cooker with lid and cook on high for 3 hours, or until the chicken reaches 165 degrees F.
Using forks, shred the chicken in the slow cooker, put the lid back on and continue to cook for another hour.
Serve over a bed of grits, rice, or mashed potatoes, or use in sandwiches. Garnish with green onions if desired.
