Tender chicken breasts slow cook in a savory homemade gravy with onion, garlic, Dijon mustard, and Worcestershire sauce. Sour cream gives the gravy a creamy finish, and there’s plenty of extra gravy for serving over mashed potatoes.
Add the chicken and onion: Place the chicken breasts in a single layer in the bottom of a 6-quart slow cooker. Sprinkle the finely diced onion over the chicken.
Make the gravy mixture: Stir together the chicken broth, garlic, Worcestershire sauce, Dijon mustard, thyme, paprika, black pepper, salt, and chicken bouillon. Pour the mixture over the chicken.
Slow cook: Cover and cook on low for 4–5 hours, until the chicken is very tender.
Shred the chicken: Remove the chicken from the slow cooker and shred it very finely with two forks. Set aside while you finish the gravy.
Thicken the gravy: Stir together the cornstarch and water to make a slurry. Stir it into the gravy in the slow cooker. Cover and cook on high for 15 minutes.
Finish the gravy: Turn off the slow cooker. Stir in the sour cream until smooth and combined. Taste and adjust the seasoning as needed.
Return the chicken: Add the finely shredded chicken back to the slow cooker and stir until well coated. Let it sit for a few minutes so the chicken can absorb some of the gravy.
Serve: Spoon the chicken and gravy over mashed potatoes and top with chopped parsley.
Notes
Onion: Dice it finely so it softens well in the slow cooker.
Chicken: Shred the chicken very finely before stirring it back into the gravy.
Gravy: It may look a little thin before the chicken goes back in. The finely shredded chicken absorbs some of the gravy as everything comes together.
Chicken thighs: Boneless, skinless chicken thighs can be substituted for the chicken breasts.