Place the chicken breasts in the slow cooker, arranging them so they aren't crowded.
In a mixing bowl, whisk together the cream of mushroom soup and chicken broth until smooth and creamy.
Pour the soup mixture evenly over the chicken, ensuring each piece is coated.
Add the sliced onion and minced garlic on top, spreading them out for aromatic flavor infusion.
Sprinkle the dried thyme, black pepper, and a pinch of salt over everything.
Cover the slow cooker with the lid and cook on low for 6 to 8 hours, until the chicken is tender and easily shredded.
Check the gravy: it should be bubbling and slightly thickened after 6 hours. If not, continue cooking for another 30 minutes.
Once cooked, carefully remove the chicken breasts and set aside on a plate.
Uncover the slow cooker and increase heat to high. Let the gravy cook uncovered for 10–15 minutes to thicken further, stirring occasionally.
Taste the gravy and adjust seasoning if needed, adding more salt or pepper for your preference.
Shred the chicken into bite-sized pieces or serve whole, then spoon the thickened gravy generously over the chicken.
Serve hot with mashed potatoes, rice, or crusty bread to soak up all that savory gravy, and enjoy a cozy, comforting meal.
