Put the knives and cutting boards away. This is one of those chicken dishes that couldn’t be any simpler. Just throw everything into the slow cooker, and leave it to work its magic. Enjoy that tropical pineapple flavor!
Coat a 6-quart slow cooker insert with cooking spray.
Place the chicken breasts into the slow cooker.
In a medium bowl, whisk together the cornstarch, brown sugar, soy sauce, orange marmalade, lime juice, ginger, salt, and pepper. Pour over the chicken.
Add the pineapple and mandarin oranges.
Cover and cook for 4–5 hours on Low or for 2–2 1/2 hours on High.