Cook the noodles per the package directions, drain, rinse with cold water, and set aside.
Combine tamari, hoisin sauce, tahini, vinegar, honey, and ⅓ cup water in a bowl and whisk.
Combine the broth with ½ cup of the tamari mixture in the same pot the noodles were cooked in. Bring to a simmer over medium heat.
Heat the sesame oil in a large skillet over medium-high heat. Add the pork and black pepper and cook, breaking it up, until browned. Add the kimchi and cook for another 2 – 3 minutes. Add the rest of the tamari mixture, bring to a simmer, and cook until the sauce coats the meat and begins to caramelize - about 5 minutes. Add the desired amount of chili crisp.
Wrap bok choy in damp paper towels and microwave for 2 minutes to steam.
Rinse noodles in hot water for about 30 seconds then divide among 4 bowls. Divide the broth between the bowls and mix with the broth. Top the pork mixture and bok choy. Add more chili crisp if desired and sesame seeds.