Crush the spices – Toast the peppercorns, coriander and cumin. Crush the spices in a mortar and pestle. Alternatively, you can use pre-ground spices, but the flavor won't be quite as fragrant.
Prepare the chicken – Cut chicken into bite size pieces, trimming off the excess fat. Mix with the spice mixture, coating the chicken pieces thoroughly.
Make the stir-fry sauce – In a separate bowl, combine the chili oil, vinegar, and the soy sauces.
Cook the noodles – In a separate pot, prepare the noodles for stir frying according to the package directions.
Cook the chicken – Spray a skillet with cooking spray and add in chicken pieces in a single layer. Cook for about 3-4 minutes on each side, or until fully cooked.
Sauté the aromatics – When the chicken is halfway done, toss in the garlic, onions, and ginger and sauté until fragrant, about 2-3 minutes.
Mix everything together – Toss in the noodles and stir fry sauce and mix together thoroughly.
Garnish and serve – Garnish with cilantro and serve with additional chili crisp if desired.