Cook the noodles in salted water per instructions.
Drain reserving 1 tablespoon of the cooking water.
While the noodles are cooking, heat the butter in a large sauté pan.
Add the shiitake mushrooms and the baby bok choy then cook, stirring occasionally, for 4-5 minutes, or until golden brown.
Add the minced garlic and ginger and cook, stirring constantly, for 1 minute.
Add the soy sauce, sesame oil, reserved pasta cooking water, and sriracha to the pan and mix well.
Add the drained noodles and toss to coat evenly.
Taste, season with sea salt, freshly cracked pepper, and sesame oil, if needed. Sprinkle the top with toasted sesame seeds.
Serve with additional sriracha and soy sauce on the side, if desired. Enjoy.