Place the chicken thighs in the slow cooker, arranging them skin side up. Season generously with salt, pepper, and dried thyme for a fragrant base.
In a mixing bowl, whisk together the cream of mushroom soup and chicken broth until smooth, creating a creamy mixture that will form the gravy.
Pour the soup mixture evenly over the chicken, ensuring each piece is well coated with the flavorful liquid.
Scatter diced onion and minced garlic over the top for added aroma and depth of flavor.
Cover the slow cooker and cook on low for 6 to 8 hours, until the chicken is fall-apart tender and the house fills with a savory aroma.
Once cooked, carefully lift out the chicken thighs and set them aside to rest. Turn the slow cooker to high for the gravy.
In a small bowl, whisk together cornstarch and cold water to make a slurry; this will thicken the gravy.
Stir the slurry into the hot gravy in the slow cooker, then cook uncovered for about 10 minutes until the gravy becomes glossy, smooth, and velvety.
While the gravy thickens, preheat your broiler to high. Arrange the chicken thighs on a baking sheet and broil for 2-3 minutes until the skin is crisp and golden.
Pour the velvety gravy over the crispy-skinned chicken and serve immediately, garnished with fresh herbs if desired for an inviting, comforting meal.
