In a blender, mix the garlic, pear, onion, spring onion, soy sauce, ground black pepper, and brown sugar. Blend for 5 minutes.
After 5 minutes, put the sliced beef in a bowl and season it with the mixture. Mix well.
Cover the bowl and refrigerate it for 30 minutes.
After 30 minutes, heat the grill pan and grill both sides of the sliced beef for 15 minutes.
Serve with fresh vegetables and enjoy!