Bring a small pot of water to a boil, carefully lower the egg into the water, and boil for exactly 6 minutes and 30 seconds for a jammy yolk.
Immediately transfer the egg to an ice bath, let cool, then peel and set aside.
Slice the pork loin into thin strips and season with the sea salt and black pepper.
In a medium pot, heat the sesame oil over medium-high heat and sear the pork strips until browned, then remove and set aside.
In the same pot, add the minced garlic and grated ginger, sautéing for 1 minute until fragrant.
Pour in the chicken broth, tamari, and sriracha, bringing the liquid to a gentle simmer.
Add the soba noodles and chopped bok choy to the broth, cooking for 4-5 minutes until the noodles are tender and the greens are wilted.
Return the pork to the pot for 1 minute to warm through.
Pour the soup into a bowl, slice the soft-boiled egg in half, and place on top.
Garnish with thinly sliced green onions and serve immediately.