Korean-Style Beef Skewers
In a large bowl, stir together soy sauce, mirin, sesame oil, ginger, sugar, garlic, green onions and hot pepper flakes. Slice beef into 48 strips about 1/8 in. (3 mm) thick and 3 in. (8 cm) long. Add beef to marinade; toss to coat. Cover and refrigerate for at least 30 minutes or up to 24 hours.
Discard marinade. Thread 2 beef strips onto each skewer. Preheat lightly oiled barbecue to medium-high. Place skewers on grill; close lid and grill until charred well, about 2 min. per side. Top with sesame seeds (if using) and serve.