**Prepare the Ground Chicken:** Heat the sesame oil in a large skillet over medium-high heat. Add the ground chicken and cook, breaking it up with a spoon, until browned and cooked through. Drain off any excess fat.
**Sauté Aromatics:** Add the chopped onion to the skillet and cook until softened, about 3-4 minutes. Stir in the minced garlic and grated ginger and cook for another minute until fragrant.
**Create the Sauce:** In a small bowl, whisk together the gochujang, soy sauce, rice vinegar, and honey (or brown sugar). Pour this sauce over the ground chicken mixture in the skillet. Stir well to coat everything evenly.
**Add Kimchi:** Stir in the 1/2 cup of chopped kimchi and the kimchi juice. Cook for 2-3 minutes, allowing the flavors to meld and the sauce to thicken slightly.
**Make the Kimchi Fried Rice:** While the chicken is finishing, heat the vegetable oil in a separate skillet or wok over medium-high heat. Add the 1/2 cup of chopped kimchi and cook for 2 minutes until slightly softened. Add the cooked rice and stir-fry, breaking up any clumps, for about 5 minutes until heated through and lightly toasted.
**Combine and Finish Rice:** Stir in half of the chopped scallions and the optional butter. Cook for another minute. Season with salt and pepper to taste.
**Assemble the Bowls:** Divide the kimchi fried rice among serving bowls. Top generously with the spicy Korean ground chicken mixture. If desired, fry the eggs sunny-side up or over-easy and place one on top of each bowl.
**Garnish and Serve:** Garnish with the remaining chopped scallions and toasted sesame seeds. Serve immediately and enjoy the vibrant flavors!