Begin by cooking the ramen noodles according to the package instructions, but skip the seasoning packets. Drain and set aside.
In a large skillet or wok, heat the sesame oil over medium heat. Add the lean ground beef and cook until browned, breaking it apart with a spatula as it cooks. This should take about 5-7 minutes. Drain any excess fat if necessary.
Once the beef is cooked, add the chopped onion, red bell pepper, broccoli florets, and shredded carrots to the skillet. Stir everything together and cook for an additional 5-6 minutes, or until the vegetables are tender but still crisp.
In a small bowl, mix together the soy sauce, brown sugar, sriracha (if using), minced garlic, and minced ginger. In another bowl, combine the corn starch and water to create a slurry.
Pour the sauce over the beef and vegetable mixture in the skillet. Add the corn starch slurry and stir well to combine. Cook for another 2-3 minutes until the sauce thickens and coats all the ingredients.
Finally, gently toss in the cooked ramen noodles, making sure they are evenly coated with the sauce and mixed well with the beef and vegetables. Cook for an additional minute to heat the noodles through.
Remove the skillet from heat and transfer the stir fry to serving plates. Garnish with sliced green onions and a sprinkle of sesame seeds for added flavor and crunch.
