If desired, warm 2 tablespoons of olive oil in a skillet over medium-high heat and brown the chicken for 3-4 minutes on each side until it develops a golden crust, then place it in the slow cooker. If skipping searing, arrange the raw chicken straight into the slow cooker.
Distribute the diced potatoes, carrots, celery, and onion evenly over the bottom of the slow cooker.
Nestle the seared or raw chicken atop the vegetable layer.
In a bowl, combine the ranch seasoning mix, minced garlic, and chicken broth, whisking until the ranch mix dissolves completely.
Dice the softened cream cheese and scatter it over the chicken and vegetables.
Pour the ranch broth mixture evenly over all ingredients, seasoning with salt and black pepper to your taste.
Cover the slow cooker and cook on low for 6-8 hours or on high for 3-4 hours without lifting the lid during cooking.
About 30 minutes before the end of cooking, stir in the heavy cream for extra richness.
Remove the chicken, shred it using two forks, then return the shredded chicken to the slow cooker and stir to incorporate it well.
If you prefer a thicker sauce, mix 1 tablespoon cornstarch with 2 tablespoons cold water, stir into the crockpot, and cook on high for an additional 15 minutes.
Garnish with freshly chopped parsley or chives if you like, and serve warm over mashed potatoes, rice, or egg noodles.
