1 pound flank steak, thinly sliced
5 tablespoons soy sauce
2 1/2 tablespoons white sugar
1/4 cup chopped green onion
2 tablespoons minced garlic
2 tablespoons sesame seeds
2 tablespoons sesame oil
1/2 teaspoon ground black pepper
Place the beef in a shallow dish. Combine soy sauce, sugar, green onion, garlic, sesame seeds, sesame oil, and ground black pepper in a small bowl. Pour over beef. Cover and refrigerate for at least 1 hour or overnight.
Preheat an outdoor grill for high heat, and lightly oil the grate.
Quickly grill beef on hot grill until slightly charred and cooked through, 1 to 2 minutes per side.