If making the anchovy and kelp stock (highly recommended), boil about 1/2 cup of water with 1 oz of kelp and 3-4 medium dried anchovies for about 20 minutes. Or you can just use water instead.
The silver skin on the belt fish can give it a very strong fishy smell- remove the skin by carefully scraping it off with a knife. You don't have to remove all of it, just remove as much as you can without putting too much effort into it. In my opinion, the fishy smell is not too bad considering we are doing other things to combat it. A lot of restaurants leave it on because it looks better.
Soak the belt fish in rice water for 30 minutes in the fridge. I always make a pot of rice to eat with galchi jorim, so just make sure to save your rice water when you are rinsing it. Rice water helps to remove the strong fishy smell.Note: if you are making this with mackerel, you can skip all the steps so far. Instead, just gut & clean your mackerel, remove the head, then cut into 2 inch steaks. The rest of the instructions are the same.
Peel and cut the Korean radish into half moons. You want them to be about 1 cm thick.
Mix the seasoning sauce ingredients together. If you can't find the ginger and plum cooking wine, you can use mirin or an equal mixture of water and soju.
Use a shallow, thick bottomed pot and arrange the Korean radish on the bottom. I always use the pattern pictured below to fit as much as possible (the Korean radish is my favorite part!).
Spread about 1/4 of the sauce over the Korean radish and pour all of the anchovy stock so the radish doesn't burn. Cover and cook on medium heat for about 5 minutes.
Uncover then flip the radishes over
Add the sliced onions on top
Add the belt fish, then spread the rest of the seasoning sauce over the beltfish. Add 2 tbsp of water to the container to collect any leftover sauce, then pour into the pot. Add the large green onions & peppers on top, then drizzle over the chili oil.Note: if it seems like there isn't enough braising liquid, don't worry! Korean radishes hold a lot of water that will be released while cooking. The radish water is slightly sweet and adds some amazing depth and flavor to the braising sauce.
Cover and cook on medium for 20 minutes, checking occasionally to spoon over the sauce and to make sure the radish doesn't burn at the bottom. After 20 minutes, turn the heat up to high for 3-4 minutes so the sauce thickens a bit.
Enjoy with a bowl of rice. The perfect bite is rice with some fish, radish, and the braising sauce :)