In a large crockpot (a four quart -- this one is a staple AND on sale :-D or six quart crock pot like this one that's oddly also marked down will do)
Layer the chicken breasts in the bottom of the crock pot.
Next, place your cream cheese on top of the chicken. When it gets warm it will spread just a bit but eventually you'll be mixing it all together with your hand mixer, so no worries that it's just set on top.
Sprinkle with the Hidden Valley ranch seasoning packet.
Cook on low for six hours.
I use my hand mixer for mixing crack chicken. Since it's hot and moist, the chicken shreds perfectly and I don't need to dirty a separate bowl. However, if you're worried about scratching your crock pot, I would definitely remove it into a different bowl before using the mixer in it, or use two forks instead. A hand mixer like this is perfect and reasonably priced. We don't need any fancy tools for this recipe!
Once you've shredded the chicken breast, sprinkle the cheese on top, then the bacon.
Put the crock pot lid back on for about 15 more minutes or just until the cheese is melted, and lastly add the scallions.