In a bowl, mix soy sauce and cornstarch. Add chicken slices and marinate for 15 minutes.
In a wok or large skillet, heat vegetable oil over high heat. Add marinated chicken and stir-fry until cooked through. Remove chicken from the wok and set aside.
In the same wok, add a little more oil if needed. Stir-fry garlic until fragrant, then add bell peppers and broccoli. Cook for 2-3 minutes until slightly tender.
In a small bowl, mix honey, sriracha sauce, rice vinegar, sesame oil, and chicken broth. Pour the sauce into the wok.
Add the cooked chicken back into the wok. Stir well to coat everything in the sauce. Season with salt and pepper to taste.
Cook for another 2-3 minutes until the sauce thickens slightly and coats the chicken and vegetables.
Garnish with sesame seeds and chopped green onions. Serve hot over steamed rice.