In a blender, combine the Asian pear, garlic, ginger, soy sauce, brown sugar, sesame oil, and chili garlic paste until very smooth. Taste the sauce, and adjust the seasonings to your preference.
Place the steak in the freezer for about 10 minutes to firm it up (this can be done while you make the sauce). When the steak is very cold, slice it thinly into about 4-inch pieces; almost as if you are shaving the meat with your knife. Place the steak strips in a shallow bowl and pour the marinade over the meat. Toss with tongs to evenly coat the steak.
Let the steak marinate at room temperature for about 20 minutes while you prepare the rest of the ingredients; veggies, lettuce, and any other toppings you'd like.
When the steak has marinated a bit, preheat a cast iron skillet (or any heavy skill you like) to medium-high heat with a drizzle of olive oil. When the oil is very hot, add some of the steak in one layer to the skillet. Don't disturb the meat for 90 seconds, then flip the steak and let it continue cooking until both sides are very browned. Continue with the rest of the meat, this may take 3 batches or so depending on the size of your skillet.
Assemble the boats with some of the beef and top evenly with the veggies and a squeeze of lime. I love these with avocado, cilantro, and lime juice.