Bring a large pot of water to a boil and cook the soba noodles for 4-5 minutes or just until tender, stirring occasionally so the noodles don’t clump. Drain in a colander and rinse well under cold water, tossing to remove the starch.
While the noodles are cooking, in a medium bowl, whisk together the soy sauce, sesame oil, rice vinegar, sugar and black pepper. Set aside.
Add the soy and sesame mixture and cook for 30 seconds, Add the noodles and toss until the noodles are heated through. Add the remaining half of the sesame seeds. Garnish with the remaining seeds and serve warm or at room temperature.