Preheat your oven to 400°F (200°C).
In a small bowl, whisk together the hoisin sauce, tamari, honey, sesame oil, grated ginger, and minced garlic to create the Char Siu glaze.
Season the pork tenderloin with sea salt and black pepper, then brush half of the glaze over the meat.
Place the pork on a parchment-lined baking sheet and roast for 15-18 minutes, or until the internal temperature reaches 145°F.
While the pork roasts, cook the soba noodles in boiling water for 4 minutes, drain, and pat them dry with a paper towel.
Heat the avocado oil in a non-stick skillet over medium-high heat. Add the noodles in a flat layer and sear for 3 minutes per side until the edges are golden and crispy.
Steam the baby bok choy for 3-4 minutes until the stalks are tender but the leaves remain bright green.
Remove the pork from the oven and let it rest for 5 minutes before slicing into medallions.
Arrange the crispy noodles and bok choy on a plate, top with sliced pork, and drizzle with the remaining glaze.
Garnish with sliced green onions and serve immediately.