Place your chicken in a single layer at the bottom of your slow cooker. Spreading them evenly ensures each piece absorbs the flavorful sauce consistently and cooks at the same rate.
Sprinkle the ranch seasoning and au jus mix evenly over the chicken. Don't worry about stirring – the slow cooking process will distribute these flavors beautifully.
Cut the butter into small pieces and scatter them across the top of the seasoned chicken. Next, arrange the pepperoncini peppers between and around the chicken pieces, then drizzle the brine over everything.
Cover and cook on LOW for 4-6 hours or HIGH for 2-3 hours. The chicken is ready when it easily shreds with two forks.
Once cooked, shred the chicken directly in the slow cooker using two forks. Mix well with the sauce, allowing each piece to soak up those incredible flavors.
If you prefer a thicker sauce, stir in the cornstarch slurry (cornstarch mixed with water) and cook on HIGH for an additional 15 minutes.