Spray liner of a slow cooker with cooking spray.
Season chicken with salt and pepper and place in a large zip-top bag. Add cornstarch to the bag, seal the bag, and toss to coat the chicken pieces. Place chicken in the bottom of the prepared slow cooker.
Salt and pepper, ¼ cup cornstarch, 4 boneless skinless chicken breasts
In a medium bowl, whisk together orange marmalade, soy sauce, sesame oil, garlic and ginger. Pour sauce over chicken. Stir to make sure that all of the chicken pieces are coated in sauce.
½ cup orange marmalade, ¼ cup soy sauce, 2 tablespoons sesame oil, 2 teaspoons minced garlic, 1 teaspoon minced fresh ginger
Cover slow cooker and cook on LOW for 3-4 hours (or on HIGH for 1 ½ - 2 hours). During the final 15 minutes of cooking, add broccoli to slow cooker. If the sauce looks too thick at this point, feel free to add water, as necessary, to reach desired consistency.
1 bag broccoli florets
Spoon chicken, broccoli, and sauce over rice. Garnish with sliced green onions and sesame seeds, if desired.
Rice, Optional: sliced green onions and sesame seeds