In a large pot of boiling water, cook ramen noodles until tender, about 3-4 minutes; rinse with cold water and drain well.
In a medium bowl, whisk together beef stock, oyster sauce, rice wine vinegar and Sriracha.
Heat sesame oil in a large skillet over medium heat. Add ground beef and onion, and cook until beef has browned, about 3-5 minutes, making sure to crumble the beef as it cooks; drain excess fat.
Stir in garlic and ginger until fragrant, about 1 minute.
Stir in beef stock mixture, scraping any browned bits from the bottom of the skillet.
Stir in ramen noodles until heated through and evenly coated in sauce, about 1-2 minutes.
Serve immediately, garnished with green onions and sesame seeds, if desired.
Notes
Prep beforehand. This stir fry recipe comes together quickly. Have all the ingredients and sauce ready to go prior to cooking.
Cook until al dente. Cook the ramen noodles just until al dente as they will continue to cook when stir-fried.
Rinse noodles with cold water. This will stop the cooking process to tighten the starches and keep the noodles from clumping.
Use lean ground beef. Opt for 90% or higher, preventing the dish from being overly greasy or oily.
Make it mild. Omit the Sriracha for milder flavors, perfect for little ones and toddlers.