Cook the soba noodles according to package directions, drain, and set aside.
In a small bowl, whisk together the tamari, honey, minced garlic, minced ginger, and Chinese five spice to create the char siu glaze.
Slice the pork tenderloin into thin medallions and season both sides with sea salt and black pepper.
Heat the avocado oil in a large skillet over medium-high heat and sear the pork medallions for 2-3 minutes per side until golden brown.
Pour the prepared glaze over the pork and simmer for 2 minutes until the sauce is thick and sticky, then remove the pork from the pan and set aside.
In the same pan, add the sesame oil and the cooked soba noodles, pressing them down with a spatula to create a crispy texture for 3 minutes.
Toss in the baby bok choy and sauté for 1-2 minutes until the leaves are vibrant green and the stems are tender-crisp.
Divide the crispy noodles and bok choy between plates and top with the caramelized pork medallions.