Cook noodles according to package instructions, rinse under cold water in a colander, and chill in the fridge for a few minutes is you can. Meanwhile, whisk peanut sauce ingredients together. Taste, adding more soy sauce (or tamari, or coconut aminos), garlic, onion, or hot sauce as desired. Toss noodles with sauce, then stir in green onion, tofu or edamame if using, and vegetables, if using.
Chef's Note: You can use buckwheat noodles in place of the whole-wheat noodles, which are completely gluten-free (despite having "wheat" in the name!). Just make sure your noodles are 100% buckwheat if you have an allergy or sensitivity. You should also use tamari in place of soy sauce.