In a medium mixing bowl, whisk together the chicken broth, orange juice, rice vinegar, soy sauce, honey, brown sugar, orange zest, red pepper flakes, ginger and black pepper.
In a 5 quart or larger slow cooker add the chicken and sauce and toss with tongs to coat all of the chicken in the sauce.
Cover and cook on LOW for 4 to 6 hours.
When the chicken is fully cooked, carefully remove the chicken from the slow cooker (it will fall apart into chunks) and place in a glass or metal dish and cover with aluminum foil to keep it warm.
Add the cornstarch to the sauce that is still in the slow cooker and whisk it into the sauce.
Add the chicken back into the slow cooker breaking up any remaining chicken that is in large chunks into smaller pieces. Make sure the sauce surrounds the chicken as best as you can.
Re-cover the slow cooker and cook on HIGH for 1 hours or until the sauce thickens.
While the sauce is thickening is a good time to prepare your rice, noodles or anything you are serving with the chicken.
Sprinkle sesame seeds over chicken when ready to serve.