Place the diced pork belly in a cold cast-iron skillet or wok over medium heat to allow the fat to render slowly.
Cook the pork belly, stirring occasionally, until the fat renders out and the meat becomes golden and crispy.
Add the minced garlic and grated ginger to the rendered fat in the pan, sautéing for about 30 seconds until fragrant.
Stir in the chopped kimchi and gochujang, cooking for 2 minutes to caramelize the kimchi and deepen the flavor.
Add the chilled jasmine rice to the pan, breaking up any clumps and pressing it down firmly with a spatula to maximize contact with the heat.
Let the rice sit undisturbed for 2-3 minutes to develop a crispy, toasted crust on the bottom.
Push the rice to one side of the pan and pour in the whisked eggs and egg whites, scrambling them until just set before folding them into the rice.
Season the mixture with sea salt and black pepper, then drizzle with toasted sesame oil for a nutty aroma.
Garnish with sliced green onions and serve immediately while the rice is at its peak crunch.