In a medium bowl, whisk all the sauce ingredients together and set aside.
Cook noodles in water according to package directions or until just tender. Drain and rinse with cold water.
In a large wok or skillet over medium high heat, add oil and cook onions until tender, about 2 minutes.
Add carrots and cook for another 2-3 minutes until carrots are tender.
Add mushrooms, cabbages and green onions and cook altogether for another 3 minutes.
Add the noodles to the pan , lower the heat to medium.
Add yakisoba sauce, mix everything together and cook for another minute or so until everything is well combined.**
Serve hot with more sauce on the side.