Dice the chicken breast into small, bite-sized pieces and season with sea salt and black pepper.
Finely chop the kimchi, garlic, and ginger, and thinly slice the green onions, separating the white and green parts.
Heat the toasted sesame oil in a large skillet or wok over medium-high heat.
Add the chicken to the skillet and cook until browned and cooked through, about 5 to 6 minutes.
Stir in the garlic, ginger, and the white parts of the green onions, sautéing for 1 minute until fragrant.
Add the chopped kimchi and gochujang to the pan, stirring to combine with the chicken and aromatics.
Fold in the cooked brown rice and coconut aminos, breaking up any clumps and stir-frying for 3 to 4 minutes until the rice is heated through and slightly crispy.
In a separate small non-stick skillet, fry the egg to your preference, ideally leaving the yolk runny.
Transfer the kimchi fried rice to a bowl, top with the fried egg, and garnish with the remaining green onion tops.