Bring a pot of water to a boil and cook the soba noodles according to package directions, reserving 2 tablespoons of the cooking water before draining.
In a large skillet over medium-high heat, add the ground pork, breaking it up with a spatula until browned and cooked through.
Stir in the minced garlic and grated ginger, cooking for 1 minute until fragrant.
Add the chopped baby bok choy to the skillet and sauté for 2-3 minutes until the leaves are wilted and the stems are tender-crisp.
In a small bowl, whisk together the tahini, tamari, chili oil, toasted sesame oil, and the reserved noodle water until smooth and creamy.
Reduce the skillet heat to low, add the cooked noodles and the creamy sauce, tossing everything together until well-coated and heated through.
Season with sea salt and black pepper, then serve garnished with sliced green onions.