How to Make It
Preheat the oven to 325°. In a large, deep ovenproof skillet, heat 2 tablespoons of the oil until shimmering. Season the pork with salt and pepper and add to the skillet, fatty side down. Cook over moderate heat, turning, until crisp and browned all over, about 20 minutes. Transfer to a plate.
Pour off all but 2 tablespoons of fat from the skillet. Add the onion, carrots, bay leaf and coriander seeds and cook over moderate heat, stirring, until the carrots just start to soften, about 5 minutes. Add 2 cups of the stock and bring to a boil. Return the pork to the skillet. Cover and braise in the oven for about 2 hours, until the meat is very tender. Transfer the pork belly to a work surface and let cool slightly, then cut each piece in half crosswise. Discard the braising liquid and vegetables and wipe out the skillet.
Meanwhile, in a shallow bowl, whisk the sugar with the vinegar until dissolved. Add the radishes and scallions and refrigerate until chilled, about 15 minutes.
In a saucepan, combine the rice grits and the remaining 2 cups of chicken stock and bring to a boil. Add a generous pinch of salt, cover partially and cook over moderately low heat, stirring, until the grits are tender and become suspended in a creamy porridge, 20 to 25 minutes. Stir in the kimchi and cream and season with salt and pepper. Keep warm over very low heat, adding 1 or 2 tablespoons of water if the grits become too thick.
In the large skillet, heat the remaining 1 tablespoon of oil until shimmering. Add the pork belly and cook over moderately high heat, turning once, until crispy, about 4 minutes. Spoon the grits into 4 shallow bowls and top with the crispy pork belly. Garnish with crushed peanuts and the pickled radishes and scallions and serve right away.
Rice grits are available at ansonmills.com, but they can also be made at home. In batches, pulse long-grain white rice in a spice grinder or blender just until very coarsely cracked, about one-third of the original size.