In a small bowl mix the sesame oil, chili oil if using, salt, and ginger together. Place the broccolini on the lined sheet pan and pour the oil mixture over the broccolini and toss to coat. Sprinkle ⅓ of the sesame seeds on the broccolini. The broccolini should be in one layer on the sheet pan. Roast for 20 minutes turning the broccolini halfway through.
While the it is roasting add the remainder of the sesame seeds to a sauté pan and heat on medium high heat stirring occasionally to toast the sesame seeds.
Once the broccolini is done sprinkle with the remaining sesame seeds.