Add 1 tablespoon of the stir fry oil to the wok (recommended) or sauté pan, set to high heat. When the oil is hot, add the 1 pound raw shrimp. Toss to coat in the oil and then turn shrimp after a few minutes once they start to get crispy on the bottom. Once opaque in color and fully cooked, toss once more to ensure even doneness and then transfer to a plate, leaving any remaining oil in the pan.
Add remaining stir fry oil to the hot wok. Add sliced 1/2 yellow onion, toss to coat in oil, then toss only to prevent browning. Once onion begins to sear, add the 8 ounces green cabbage and 1 1/2 cups celery. Toss to coat in oil once again, then allow to cook for a couple of minutes to brown. Toss to prevent burning.
While the veggies are cooking, run the noodles under hot water for a minute or two so that they separate. Alternatively, you can place them in a bowl of warm water.
Just before veggies are done, add 2 cloves garlic and 1/2 teaspoon ginger, toss, and allow to cook for about a minute. Transfer to a separate plate.
Add the 1 tablespoon toasted sesame oil to the hot pan and add rinsed 21 ounces refrigerated yakisoba noodles. Be sure to shake off as much excess water as possible. Be extra careful—any water that hits the hot oil will pop. Allow to cook for a minute or so, undisturbed, so that the noodles on the bottom crisp up a bit.
Add the cooked shrimp and veggies back in with he noodles and toss to combine.
Add 3 tablespoons soy sauce and 2 tablespoons oyster sauce, toss to combine, and allow to cook just until heated through.