In a bowl, combine the cucumber, ¼ cup rice vinegar, granulated sugar, and salt. Toss well and set aside to pickle while you prepare the rest of the meal.

Rinse the jasmine rice until the water runs mostly clear. Add it to a saucepan with 1½ cups water. Bring to a boil, cover, and reduce the heat to low. Cook until tender, following the rice package timing, then keep covered off the heat.

Preheat the smoker to 250°F using wood pellets. In a large bowl, gently mix the ground beef, egg, panko, 2 tablespoons chopped green onion, garlic, ginger, 1 tablespoon soy sauce, gochujang, ½ tablespoon brown sugar, and ½ teaspoon sesame oil. Shape the mixture into four small oval loaves.

Place the mini meatloaves on the smoker rack with space between them. Smoke until the centers reach 160°F on an instant-read thermometer, checking the thickest part of each loaf.

While the meatloaves smoke, stir together the remaining 1 tablespoon soy sauce, ½ tablespoon brown sugar, rice vinegar, honey, and remaining ½ teaspoon sesame oil. Brush the mixture over the meatloaves during the final 10 minutes of smoking.

Fluff the cooked rice with a fork and stir in the sesame seeds. Serve each meatloaf over sesame rice with the pickled cucumbers on the side. Finish with the remaining chopped green onion.