Arrange the chicken thighs in the bottom of your slow cooker insert (minimum 3-quart size recommended).
Sprinkle the homemade ranch seasoning and garlic powder evenly over the chicken.
Distribute the cubes of cream cheese over the top of the seasoned chicken.
Secure the lid on the slow cooker. Cook on the LOW heat setting for 3 to 4 hours, or on the HIGH heat setting for 1.5 to 2.5 hours, until the chicken is cooked through and very tender. Avoid lifting the lid during the cooking cycle.
Once the cooking time is complete, use two forks to shred the chicken directly within the slow cooker insert. The chicken should shred very easily.
Stir the shredded chicken thoroughly, incorporating the melted cream cheese until a creamy sauce forms and coats the chicken evenly.
Stir in the crumbled cooked bacon. If using, stir in the optional hot sauce now.
Spread the chicken mixture into a relatively even layer within the slow cooker. Sprinkle the shredded cheddar cheese uniformly over the top.
Place the lid back on the slow cooker and let it sit for about 10 minutes, or just until the cheddar cheese is fully melted and gooey.
Serve the cheesy bacon ranch chicken hot, garnished generously with the sliced green onions.