Prep for success: Lightly grease the slow cooker insert if you want easier cleanup. Pat the chicken dry with paper towels so the seasoning sticks and the sauce doesn’t turn watery.
Season evenly: Sprinkle salt, pepper, garlic powder, and onion powder over both sides of the chicken. Press the seasoning in with your hands so it adheres. If the breasts are very thick, you can cut them in half lengthwise for faster, more even cooking.
Optional flavor step (recommended if you have time): Heat a skillet over medium-high heat. Sear the chicken 1–2 minutes per side until you see light golden spots. This does not cook the chicken through; it just adds a deeper, savory flavor.
Build the sauce base: Pour chicken broth into the slow cooker. Add the ranch seasoning (and Dijon mustard if using). Whisk well for 20–30 seconds until the seasoning is mostly dissolved. This prevents gritty seasoning pockets later.
Add the chicken: Place the seasoned chicken into the slow cooker in as even a layer as possible. If pieces overlap, that’s fine—just make sure the chicken is touching the liquid.
Add cream cheese correctly: Scatter the cubed cream cheese over the top of the chicken. Do not stir yet. Letting it melt slowly on top helps it blend smoothly and keeps the sauce creamy.
Cook (choose your timing): Cover and cook on LOW for 4–6 hours or HIGH for 2½–3½ hours. Cook time depends on chicken thickness and your slow cooker. The chicken should reach 165°F / 74°C and feel very tender when pierced.
Check tenderness before shredding: Lift a piece with tongs and try shredding with a fork. If it resists or feels rubbery, cook 20–30 minutes longer on LOW (or 10–15 minutes on HIGH) and test again. Shreddable chicken = tender chicken.
Shred the chicken: Shred directly in the slow cooker with two forks, or remove to a plate, shred, and return. Aim for bite-size strands so the sauce coats everything evenly.
Stir until silky: Stir slowly but thoroughly to blend the melted cream cheese into the cooking liquid. Keep mixing until the sauce looks smooth and creamy with no large cream cheese pieces. If you see small soft bits, keep stirring for 30–60 seconds—they will melt in.
Add sour cream at the end: Switch the slow cooker to WARM (or turn it off). Stir in the sour cream until fully combined. Adding it at the end keeps the sauce silky and helps prevent dairy separation.
Adjust sauce thickness: If the sauce is thicker than you want, stir in 1–3 tablespoons warm broth until it loosens. If the sauce is too thin, leave the lid off and cook on HIGH for 10–15 minutes, stirring once or twice, to thicken slightly.
Serve: Spoon creamy ranch chicken over rice, mashed potatoes, or egg noodles. Finish with chopped parsley or chives and cracked black pepper if desired. Serve with a green veggie to balance the richness.