Step 1: In a large bowl, whisk together the grated Korean pear (or apple), soy sauce, brown sugar, minced garlic, grated ginger, sesame oil, and black pepper. If making a spicy version, add gochujang and gochugaru and whisk until well combined.
Step 2: Add the beef slices to the marinade, ensuring all pieces are thoroughly coated. Gently massage the marinade into the meat.
Step 3: Cover the bowl tightly or transfer the marinated meat to a large resealable bag or Basics Glass Food Storage container. Refrigerate for at least 4 hours, or ideally overnight (12-24 hours) for the best flavor and tenderness.
Step 4: About 20-30 minutes before grilling, remove the marinated beef from the refrigerator to allow it to come closer to room temperature.
Step 5: Preheat your indoor electric grill, outdoor charcoal, or gas grill to medium-high heat (approximately 375-400°F / 190-200°C). Lightly oil the grill grates to prevent sticking.
Step 6: Place the marinated beef slices on the hot grill in a single layer, making sure not to overcrowd. Cook the bulgogi for 1-2 minutes per side, or the galbi for 3-4 minutes per side, until desired doneness and a nice char develops.
Step 7: Transfer the cooked meat to a serving platter. Continue grilling the remaining meat in batches until all is cooked.
Step 8: Serve the hot, grilled Korean BBQ beef immediately with fresh lettuce leaves, steamed white rice, and your favorite banchan. Encourage guests to create ssam (lettuce wraps) with the meat, rice, and side dishes.