Place the diced pork belly in a cold large skillet or wok and turn the heat to medium-high.
Cook the pork belly for 8-10 minutes, stirring occasionally, until the fat has rendered and the meat is deeply browned and crispy.
Remove the pork belly from the pan with a slotted spoon and set aside, leaving 1 tablespoon of the rendered fat in the pan.
Add the minced garlic, grated ginger, and the whites of the scallions to the pan, sautéing for 1 minute until fragrant.
Stir in the chopped kimchi and gochujang, cooking for 2 minutes to caramelize the sugars and intensify the flavor.
Add the chilled jasmine rice to the pan, breaking up any clumps, and stir to coat every grain in the kimchi sauce.
Press the rice firmly into the bottom of the pan and let it sit undisturbed for 3-4 minutes to develop a crunchy, toasted bottom layer.
While the rice crisps, fry the egg in a separate small non-stick pan until the whites are set but the yolk remains runny.
Stir the crispy pork belly back into the rice along with the tamari, sea salt, and black pepper.
Serve the fried rice in a bowl topped with the fried egg and the remaining green scallion tops.