You can freeze cooked chicken yakisoba in a freezer-safe container - like FoodSaver's Preserve & Marinate Containers - or bag for up to one month. However, this dish is best eaten fresh, within five days. Freezing tends to diminish the flavors of the dish. If you do freeze yakisoba, allow it to that in the refrigerator overnight. You'll also want to add some yakisoba sauce, or even plain soy sauce or teriyaki sauce, to the dish when reheating in the microwave or stovetop.