Using kitchen scissors, trim the fins from both sides of the beltfish pieces.

Clean the inside of the fish, removing any guts and blood clots.

Rinse the cleaned fish pieces thoroughly under cold running water.

Pat the fish dry with paper towels to remove excess moisture.

Peel and slice the radish into quarter-inch thick rounds, then cut some into halves or quarters.

Slice the onion thinly.

Mince the garlic and ginger.

In a mixing bowl, combine the minced garlic, ginger, soy sauce, gochugaru (hot pepper flakes), and black pepper. Mix well to create the seasoning sauce.

In a heavy-bottomed pot, create a layer with the sliced radish, followed by a layer of sliced onion.

Place the beltfish pieces on top of the onions.

Evenly spread the seasoning sauce over the fish.

Rinse the sauce bowl with 2 cups of water and pour the water into the pot along the edges.

Cover the pot, bring it to a boil, and cook over medium-high heat for 15 minutes.

Slice the green chili pepper and green onion.

After 15 minutes, add the sliced green chili pepper and green onion to the pot. Spoon some of the broth over the fish.

Cover again, reduce the heat to medium, and cook for another 15 minutes.

Reduce the heat to low, spoon more broth over the fish, cover, and simmer for another 5 minutes until the radish is soft and the sauce has thickened.

The Galchi-jorim is done. Carefully transfer the fish, radish, and onion to a serving plate, and pour the remaining sauce over the top.

Serve hot with freshly made rice.