In a small pot, bring water to a boil and cook soba noodles for 5-6 minutes until al dente, then drain and set aside.
Season the pork tenderloin with sea salt and sear in a pan over medium-high heat until browned on all sides.
Add the bone broth, tamari, minced garlic, and grated ginger to the pan with the pork; cover and simmer for 10-12 minutes until cooked through.
While pork braises, soft-boil the egg in a separate pot for 6.5 minutes, then immediately transfer to an ice bath and peel.
Steam the baby bok choy in the last 3 minutes of the pork's cooking time until the leaves are bright green.
Whisk the toasted sesame oil, chili flakes, and rice vinegar together in a small bowl to create the chili oil.
Slice the pork thinly and halve the soft-boiled egg.
Assemble the bowl by placing noodles at the bottom, topping with pork, egg, and bok choy, then drizzling with the spicy chili oil.