Place the chicken thighs in the bottom of your slow cooker.
In a separate bowl, whisk together the honey, soy sauce, orange marmalade, hoisin sauce, garlic, ginger, sriracha, onion, sesame oil and red pepper flakes.
Pour sauce over chicken breasts, and turn them so they're coated in the sauce.
Cover and cook on LOW for 4-6 hours until the chicken is cooked through.
Remove chicken, keeping liquids in the slow cooker, and place chicken in a bowl. Shred chicken using two forks, hand mixer, or whichever method you prefer.
In a small bowl, whisk together the cornstarch with water. This is called a slurry, and it will thicken the sauce.
Transfer the liquids from the slow cooker to a small saucepan over medium high heat and whisk in the cornstarch mixture. Bring sauce to a boil, then simmer until it reduces and thickens slightly. This took me about 3-4 minutes.
Alternatively, you can add the cornstarch mixture directly to the liquids IN the slow cooker. Whisk and turn slow cooker on HIGH. Whisk occasionally until sauce thickens.
Pour half the sauce over shredded chicken and toss to combine. Top chicken with scallions and sesame seeds.
Reserve the second half of the sauce for drizzling over the chicken as desired.