Combine sesame
seeds, sesame oil, vinegar, soy sauce, oil and brown sugar in a
large bowl
Stir in garlic, green onions, pepper and pepper
flakes
Add beef cubes, cover and refrigerate 6 to 8 hours.
Remove beef from marinade and thread on the kebob skewers
and rotate 15 minutes or until beef is browned on the outside but
still pink inside.