Whisk all together; whisk soy sauce, chicken broth, chili sauce, rice vinegar, sesame oil, honey, cornstarch, and garlic in a small bowl. Set aside.
Prepare the noodles:
Cook the noodles; cook the noodles according to package directions. While the noodles are cooking, prepare the beef.
Prepare the steak:
Slice the steak; slice the steak with a sharp knife into thin slices. Season the beef with salt and pepper.
Heat olive oil in a large skillet. Add the beef and cook until browned, for 2-3 minutes. You may need to do this in batches, because the beef must not touch.
Add remaining:
Add the sauce; pour the prepared sauce over the beef. Stir and simmer until the sauce reduces and slightly thickens.
Drain the cooked noodles and add them to the skillet. Toss everything together.
Serve:
Serve the beef and noodles garnished with spring onions, red pepper flakes, and sesame seeds.
Notes
If you want some greens in this dish, you can add baby spinach with the noodles. Cook the spinach until it just wilts.