01 -
Put chicken breasts into a 4-5 quart slow cooker. Lay them flat, side by side.
02 -
Mix barbecue sauce (1 cup), vinegar, sugar, garlic powder, onion powder, and red pepper flakes in a small bowl using a whisk.
03 -
Pour sauce all over the chicken inside the slow cooker. Make sure it’s fully covered. Put the lid on and cook on LOW for 4-5 hours until the chicken is tender, juicy, and hits 165°F inside.
04 -
Lift the lid and spread the leftover ½ cup of barbecue sauce on top of the cooked chicken.
05 -
Leave the lid off, switch to HIGH, and let it cook for another 30-45 minutes. This step makes the sauce thicker.
06 -
Turn off the slow cooker. Move the chicken to a serving dish. If you like, sprinkle some chopped parsley on top before serving.