01 - In a mixing bowl, whisk together gochujang, soy sauce, brown sugar, sesame oil, minced garlic, grated ginger, rice vinegar, mirin, and black pepper until a smooth, homogeneous paste forms.
02 - Place the trimmed lamb ribs in a large resealable bag or shallow dish. Pour the marinade over the ribs, massaging it into every surface to ensure even, thorough coating. Seal tightly and refrigerate for a minimum of 4 hours, preferably overnight for deepest flavor penetration.
03 - Preheat the oven to 320°F. Remove the ribs from the refrigerator and transfer them from the marinade to a wire rack set over a rimmed baking sheet, reserving any leftover marinade. Tightly cover the rack with aluminum foil to trap moisture during the slow roast.
04 - Roast the covered ribs for 1 hour. While the ribs cook, pour the reserved marinade into a small saucepan, stir in the honey, and simmer over low heat for approximately 5 minutes until the mixture thickens into a glossy glaze. Remove from heat and set aside.
05 - Increase the oven temperature to 400°F. Uncover the ribs and brush them generously on all sides with the honey-gochujang glaze. Return the ribs to the oven uncovered and roast for 10 to 15 minutes, until the surface is deeply caramelized with lightly charred edges.
06 - Remove the ribs from the oven and allow them to rest for 5 minutes so the juices redistribute. Squeeze yuzu juice generously over the entire surface of the ribs for a bright, citrusy finish.
07 - Scatter sliced scallions, toasted sesame seeds, and sliced red chili over the ribs. Cut between the bones into individual ribs and serve immediately alongside steamed rice or pickled vegetables.