Step 1

Mix together scallion, miso, gochujang, sugar, oil, sesame seeds, and 1 tsp. water in a small bowl.

Step 2

Trim scallions and slice in half lengthwise. Cut crosswise into 3" lengths, then slice pieces lengthwise as thinly as possible into matchsticks. Rinse under cold water; drain well and pat dry. Transfer scallions to a medium bowl; add oil, vinegar, and sesame seeds and toss to combine.

Step 3

Mix ginger, garlic, soy sauce, vinegar, brown sugar, gochugaru, and sesame oil in a medium bowl to combine.

Step 4

Using a sharp knife, slice short ribs at a steep angle every ¼", cutting no more than halfway through meat. Turn over and slice on the second side, maintaining the same angle as the first side (this helps to keep meat in 1 piece by minimizing the danger of slicing all the way through). Place meat inside bowl with marinade and toss well to coat, working marinade into slashes in meat. Cover bowl with a large plate and let sit at room temperature at least 2 hours or chill up to 1 day.

Step 5

Prepare a grill for medium-high heat; oil grate with vegetable oil. Remove short ribs from marinade and very lightly season with salt. Grill, turning every 1–2 minutes and moving to a cooler part of grill if needed, until meat is firm to the touch and peeking inside deepest slashes shows just a streak of pink (cooking the meat to at least medium helps build flavor and yields the best texture), 8–10 minutes.

Step 6

Transfer short ribs to a cutting board and let rest at least 5 minutes before slicing across the slashes—or frankly, just tear it apart.

Step 7

Season scallion salad with salt. Serve short ribs with scallion salad and ssamjang, wrapped in lettuce if desired.