Step 1

Blitz garlic, Asian pear, and ginger to a smooth purée in a food processor or blender. (Or, finely grate garlic and ginger; grate Asian pear on large holes of a box grater.) Transfer purée to a medium bowl. Whisk in mirin, soy sauce, sugar, sesame oil, black pepper, and ½ cup water until sugar is dissolved.

Step 2

Arrange short ribs in a resealable plastic bag or baking dish. Pour marinade over and turn ribs to coat. Seal or cover and chill at least 4 hours and up to 12 hours.\Do Ahead: Freeze ribs in marinade for up to 1 month.

Step 3

Slice scallion pieces lengthwise into thin strips. Soak in a mesh strainer set inside a large bowl of ice water 10 minutes to remove some sharp bite and allow time to curl slightly. Swish scallions around with your hands to remove any sliminess, then drain well and pat dry. Wipe out bowl; return scallions to bowl.

Step 4

Whisk vinegar, mirin, gochugaru, and sugar in a small bowl until sugar is dissolved; season with salt. Add dressing to scallions and toss to coat.

Step 5

Prepare a grill for medium-high heat; oil grate. Remove short ribs from marinade and grill until well browned and slightly charred around edges, about 3 minutes per side. Transfer to a platter and top with sesame seeds and sliced scallions. Let rest 5 minutes, then cut meat into bite-size pieces with kitchen shears.

Step 6

Arrange lettuce and perilla leaves (if using) on a second platter. Scoop rice into individual bowls.

Step 7

To eat, stack a palm-size lettuce leaf and a perilla leaf in your hand. Top with rice, meat, and scallion salad and wrap into a tight bundle. Eat in one bite and repeat!