Place chicken breasts in the slow cooker and sprinkle with Ranch seasoning mix.
Top chicken with the block of cream cheese. Cover and cook on HIGH for 2.5-3 hours or LOW for 4-5 hours until chicken is cooked through.
Remove lid and shred the chicken inside the slow cooker using two forks.
Stir in ¾ of the chopped bacon and 1 cup shredded cheddar cheese into the shredded chicken.
Prepare baked potatoes by washing and drying them. For oven method, preheat oven to 425°F, rub potatoes lightly with olive oil, season with salt and pepper, and bake on a foil-lined baking sheet for 45-60 minutes until tender. Let cool 5-10 minutes.
Alternatively, microwave potatoes on full power for 7 minutes, turning once, continuing in 1-minute increments until fork-tender. Let rest 5-10 minutes.
Preheat oven broiler and line a baking sheet with foil.
Make a lengthwise slit on each potato without cutting fully through. Gently fluff the insides with a fork and season with salt and pepper.
Add a small pat of butter inside each potato, then stuff with the chicken mixture.
Top each stuffed potato with 1 tablespoon shredded cheddar cheese and remaining chopped bacon.
Broil potatoes for about 5 minutes until cheese is melted and bubbly. Watch carefully to avoid burning.
Remove from oven and let rest for 5 minutes before serving.
Garnish with fresh chopped chives and a drizzle of Ranch dressing if desired. Serve warm.