In a medium bowl, toss chicken pieces with 2 tablespoons soy sauce and 1 tablespoon cornstarch until well coated. Let marinate for 10 minutes.
While chicken marinates, cook noodles according to package directions. Drain and set aside.
In a small bowl, whisk together 1/4 cup soy sauce, honey or maple syrup, rice vinegar, minced garlic, grated ginger, 1 tablespoon cornstarch, and water or chicken broth. Set aside.
Heat 1 tablespoon vegetable oil in a 12-inch skillet or wok over medium-high heat. Pat chicken dry with paper towels, add to skillet in single layer, and cook until golden and cooked through (about 5-7 minutes total), reaching 165°F internally. Remove from skillet and set aside.
In the same skillet, heat remaining 1 tablespoon oil. Add mixed vegetables and stir-fry for 3-4 minutes until crisp-tender.
Add cooked noodles and chicken back to skillet. Pour sauce over everything and toss to combine. Cook for 2-3 minutes until sauce has thickened and coats the back of a spoon.
Garnish with sliced green onions and sesame seeds before serving.
Notes
Don’t overcrowd the pan when cooking chicken to ensure proper browning. Use a meat thermometer to check for 165°F internal temperature.
Fresh garlic and ginger provide much better flavor than jarred versions.
Feel free to add other vegetables like snap peas, mushrooms, or water chestnuts for variety.
For extra heat, add a pinch of red pepper flakes to the sauce.
If sauce becomes too thick, add a splash of water or chicken broth to loosen it.
Slightly undercook noodles if making ahead, as they’ll soften more when reheated.