Prepare the IngredientsWash and chop all vegetables. Mince the garlic.
Boil the Noodles and BroccoliBreak spaghetti noodles in half and cook according to package directions in salted water. Add the broccoli florets during the last 4 minutes of cooking. Drain and set aside.
Brown the BeefIn a large skillet or wok over medium heat, cook the ground beef with the onion and celery until the beef is browned and the vegetables are tender. Drain any excess fat.
Add More VeggiesStir in the bell pepper, carrots, garlic, mushrooms, bean sprouts, and water chestnuts. Cook for 4–5 minutes, stirring occasionally, until vegetables are crisp-tender.
Combine and SeasonAdd the drained noodles and broccoli to the skillet. Stir in the soy sauce, sugar, ground ginger, sriracha, and sesame oil (if using). Toss everything together until evenly coated and heated through.
Serve HotServe immediately. Garnish with sesame seeds if desired.