Chop up the vegetables and chicken. Whenever I know I'm making a dish that requires a good amount of chopping, I chop my veggies the night before, cover them in plastic warp and refrigerate them. This really speeds up the cooking processes.
Heat olive oil in a large wok over medium high heat. Add the minced garlic and stir for about 1 minute.
Place the diced chicken into the wok and stir until light brown and most of the liquid is absorbed.
Add the chopped onions, and sauté them until they become translucent.
Toss in the carrots and celery and stir until softened. Then add in the cabbage, bell pepper, and broccoli and stir for about 4 minutes.
Pour in rice vinegar and soy sauce and sprinkle in the sugar. You may want to add a little more soy sauce depending on how salty you prefer your food.
Add in the Yakisoba noodles. The noodles might be very compact at first, but they will separate after they sit in the hot wok for a few minutes.
Stir the noodles for another 3-5 minutes or until they've all separated. Remove from heat and serve warm.