Heat a large skillet or wok over medium-high heat. Add the ground chicken and cook until browned, breaking it up with a wooden spoon, about 5-7 minutes.
Add the minced garlic and ginger to the skillet and cook for an additional 1-2 minutes until fragrant.
Stir in the coleslaw mix and green onions, cooking until the cabbage is tender, about 3-4 minutes.
In a small bowl, mix together the soy sauce, sesame oil, rice vinegar, hoisin sauce, and red pepper flakes (if using). Pour this sauce over the chicken and vegetable mixture.
Stir well to combine and cook for another 2-3 minutes to heat everything through and allow the flavors to meld.
Serve hot, garnished with sesame seeds and additional sliced green onions if desired.