Bring a small pot of water to a boil, carefully lower the egg into the water, and simmer for 6.5 minutes before transferring to an ice bath.
In a separate pot, cook the soba noodles according to the package instructions until al dente, then drain and set aside.
Heat the sesame oil in a large saucepan over medium-high heat and add the ground pork, breaking it apart with a spatula.
Stir in the grated ginger and minced garlic, cooking until the pork is browned and the aromatics are fragrant.
Season the pork with sriracha, sea salt, and black pepper, then pour in the beef broth and bring to a gentle simmer.
Add the baby spinach to the broth and stir for one minute until the leaves are bright green and wilted.
Divide the noodles into a bowl, pour the spicy pork and broth mixture over them, and top with the halved jammy egg and sliced green onions.