Cook noodles according to directions on the package (most will recommend cooking in boiling water from 5-8 minutes. It depends on the brand).
While the noodles are cooking, slice up the celery and green onions.
Combine soy sauce, rice vinegar, and sesame oil in a large bowl.
Pour the cooked noodles in a strainer in the sink, and rinse instantly with cold water until the noodles have cooled.
Add noodles to the sauce in the bowl, add celery and green onions, and gently toss to coat.
Top with sesame seeds and cooked proteins if desired.
Notes
Store for up to 4 days in the fridge in an air-tight container.The noodles can dry out after a few days. A splash of rice vinegar perks them right back up!