Season chicken with salt, pepper, paprika, and onion powder and arrange in the slow cooker.
In a medium bowl, stir sour cream, condensed cream of mushroom soup, chicken broth, and minced garlic and until fully combined. Stir in the fresh sliced mushrooms.
Pour the mushroom sauce over the chicken. Cover and cook for 4 hours on HIGH or 6 hours on LOW.
Garnish with fresh minced parsley (optional) before serving.
Slicing the chicken breasts in half (butterflying) will allow them to cook faster.Store leftovers covered in the fridge for up to 3 days.
Which type of chicken should I use? I use boneless skinless chicken breasts. If you are short on time, you can butterfly the breasts and they will cook in 2-3 hours on HIGH - likely even sooner. Just make sure it reaches as safe temp of 165°.
Should I use fresh mushrooms? I use fresh sliced mushrooms. You can find them in the produce section, pre-washed and pre-sliced which make them really convenient. You can also use canned mushrooms if that’s what you have on hand or prefer.
How to thicken mushroom gravy: If the sauce is too thin for your taste, add a little bit of cornstarch slurry. In a small bowl, whisk together 1 tablespoon of cornstarch and 1-2 tablespoon of water. Pour this into the crockpot and give it a stir. Cover and continue cooking on low for 10 minutes or until thickened. It should thicken pretty quickly.
Does sour cream curdle in the slow cooker? Unfortunately, yes, sour cream doesn't always play nicely with the slow cooker but the good news is, even though it isn't pretty, it still tastes great. To prevent curdling, you can add the sour cream in at the end of the cook time next time - scoop out a bit of the broth, whisk in the sour cream to the broth to warm it up, then pour it all back into the slow cooker and stir. I'm also told you can whisk in a couple tablespoons of flour to the mixture before cooking to prevent it from happening, but I haven't tested that yet.