In a mixing bowl, combine the minced pear, minced garlic, grated ginger, soy sauce, sesame oil, sriracha, lime juice, brown sugar, onion powder, and black pepper. Whisk together until the brown sugar has dissolved and all ingredients are well incorporated.
Place the thinly sliced flank steak in a large resealable plastic bag or a shallow dish. Pour the marinade over the beef, ensuring each piece is well coated. Seal the bag or cover the dish, and refrigerate for at least 30 minutes, or up to 4 hours for maximum flavor.
When you're ready to cook, heat a large skillet or griddle over medium-high heat. Add the vegetable oil to the pan and let it warm until shimmering.
Remove the marinated beef from the refrigerator and let any excess marinade drip off. In batches, add the beef to the hot skillet in a single layer. Cook for about 2-3 minutes on each side, or until the beef is nicely browned and cooked through. Avoid overcrowding the pan to ensure a good sear.
Once cooked, remove the beef from the skillet and let it rest for a few minutes. Serve the Korean Beef Bulgogi with steamed rice, lettuce wraps, or alongside your favorite Korean side dishes like kimchi or pickled vegetables. Enjoy the explosion of flavors!
