Preheat oven to 375 degrees F (190 degrees C). Toast sesame seeds for 3 to 5 minutes, or until the seeds begin to turn golden brown. Set aside.
Bring a large pot of water to a boil. Cook broccoli in boiling water for 3 to 5 minutes, or until desired tenderness. Drain, and transfer to a large bowl.
In a small bowl, whisk together the vinegar, soy sauce, sesame oil, sugar, and sesame seeds. Pour over broccoli, and toss to coat.
