Boil soba noodles according to package instructions (usually 4–5 minutes). Drain and rinse under cold water to stop cooking. Toss with a small amount of sesame oil to prevent sticking. Set aside.
In a large skillet, sauté mushrooms in a splash of sesame oil for a few minutes. Add snap peas; cook 2–3 minutes until crisp-tender.
In a small bowl, whisk together miso paste, soy sauce, rice vinegar, sesame oil, ginger, and water until smooth.
Add the noodles and sauce to the pan with veggies. Toss well until everything is coated and warmed through.
Top with green onions and (optional) sesame seeds. Add tofu or edamame if you’d like extra protein.
