In a medium bowl, whisk together peanut butter, soy sauce, garlic, honey, ginger, vinegar, sesame oil and Sriracha, if using; set aside.
In a large pot of boiling water, add Yaki-Soba until loosened, about 1-2 minutes; drain well.
Heat olive oil in a large skillet over medium heat. Add chicken to skillet and cook until golden, about 3-4 minutes.
Stir in cabbage, carrots and green onions until heated through, about 1 minute.
Stir in Yaki-Soba and peanut butter mixture until well combined, about 2 minutes.
Serve immediately, garnished with cilantro and peanuts, if desired.
