Boil noodles just until al dente. Drain, toss with a drizzle of sesame oil, and set aside.

Heat 1 tbsp oil in a wok or large skillet over medium-high heat. Add chicken in a single layer, sear until browned and cooked through. Remove and set aside.

Add the remaining oil to the pan. Sauté garlic and ginger until fragrant.

Add vegetables, starting with harder ones like carrots and broccoli, then add softer ones like bell peppers and snap peas. Stir-fry until crisp-tender.

In a small bowl, whisk soy sauces, oyster sauce, chicken broth, sesame oil, and sugar. Pour the sauce into the pan and let it bubble briefly.

Return chicken and add drained noodles. Toss everything together until coated and heated through. Taste and adjust seasoning if needed.

Garnish with green onions and sesame seeds. Serve hot.