In a small bowl, whisk together soy sauce, oyster sauce, brown sugar, ginger, garlic, sesame oil and Sriracha; set aside, reserving 2 tablespoons.
In a large bowl, combine reserved 2 tablespoons soy sauce mixture and chicken; set aside.
In a large pot of boiling salted water, cook pasta according to package instructions. Within the last 2 minutes of cooking time, add broccoli; drain well.
Heat olive oil in a large skillet or wok over medium high heat. Add chicken to the skillet and cook until golden, about 2-3 minutes. Stir in pasta, broccoli and remaining soy sauce mixture until heated through, about 2 minutes.
Serve immediately, garnished with parsley and sesame seeds, if desired.