Instructions:

1. Prepare the ingredients
   Step 1:

   Slice the chicken breast and prepare all the vegetables as indicated in the ingredients list.
2. Stir fry the chicken
   Step 2:

   Heat vegetable oil in a wok or large skillet over medium-high heat. Add the sliced chicken and stir fry until it’s cooked through and lightly browned. Remove the chicken from the wok and set it aside.
3. Stir fry the vegetables
   Step 3:

   In the same wok, add a bit more vegetable oil if needed. Stir fry the thinly sliced onion, red bell pepper, green bell pepper, julienned carrots, and minced garlic until they become tender-crisp.
4. Prepare the sauce
   Step 4:

   In a small bowl, mix together soy sauce, hoisin sauce, oyster sauce, rice vinegar, sesame oil, and red pepper flakes (if using).
5. Combine everything
   Step 5:

   Add the cooked chicken back into the wok with the stir-fried vegetables. Pour the sauce over the chicken and vegetables, and toss everything together until well-coated and heated through.
6. Serve and garnish
   Step 6:

   Garnish with chopped green onions and cilantro. Serve the Chicken Stir Fry New York Style hot over steamed rice or noodles.