In a bowl, mix 1 cup of Catalina salad dressing, 1 cup of peach jam, and 1 packet of dry onion soup mix.
Add 2 lbs of boneless chicken breasts (about 4 pieces) to the slow cooker. Pour the sauce overtop of the chicken and stir it together.
Cover and cook on low for 5-6 hours or on high for 3-4 hours, or until the chicken reaches an internal temperature of 165°F when you poke it with a meat thermometer. Spoon the sauce over the chicken every hour if possible.
In the last 30 minutes of cooking, mix 2 Tbsp of cornstarch with 2 Tbsp of cold water to form a slurry. Stir this into the sauce to thicken it. Close the lid and let it cook that last 30 minutes.
Once cooked, turn off the heat. Remove the chicken from the slow cooker and shred it with two forks. Stir it back into the slow cooker sauce. Serve the chicken over rice or pasta, drizzling more sauce on top. Enjoy!