Method
Cut the onions in half, then slice each half into 3 pieces.
Mix all pickling sauce ingredients in a bowl until well combined.
Preheat a frying pan, add cooking oil, and grill the onions over medium-low heat until golden brown.
Finely chop the chili peppers and green onion.
Place the grilled onions and chopped chili peppers in a large jar or container. Pour the pickling sauce over them.
Sprinkle sesame seeds on top and refrigerate for 24 hours. This allows the spiciness to mellow and the soy-based sauce to deeply infuse the onions.
Serve as a side dish on rice or with Korean BBQ. Delicious and flavorful!