Bring a small pot of water to a boil; carefully lower the egg into the water and simmer for 6.5 minutes, then immediately transfer to an ice bath.
Cook the soba noodles in a separate pot according to package directions, drain, and set aside.
Heat the toasted sesame oil in a large skillet or wok over medium-high heat and brown the ground pork with sea salt and black pepper until fully cooked.
Add the minced garlic, grated ginger, and sliced shiitake mushrooms to the skillet, sautéing for 2 minutes until the mushrooms are softened and fragrant.
Pour in the chicken bone broth, tamari, and sriracha, bringing the mixture to a gentle simmer.
Add the chopped baby bok choy to the broth and cook for 2 minutes until the leaves are bright green and the stems are tender-crisp.
Peel the cooled egg and slice it in half lengthwise to reveal the jammy yolk.
Place the cooked soba noodles in a deep bowl, pour the pork and spicy broth over the top, and garnish with the jammy egg halves and sliced green onions.