Whisk the soy sauce, sesame oil, sriracha sauce, garlic, sesame seeds and rice vinegar until blended. Set aside.
Bring a large pot of slightly salted water to a boil
Add the sprouts and cook uncovered for about 15 seconds until tender crisp
Remove from the water with a strainer and immerse in ice water until cold, at least five minutes
Remove from the ice water with a strainer and transfer to a bowl
Add the reserved sauce and toss to coat
Garnish with green onions and serve