Step 1
Preheat your oven to 375°F (190°C). Lightly grease a 9×13-inch baking dish with cooking spray or a thin layer of oil to prevent sticking.

Step 2
Heat sesame oil and vegetable oil in a large skillet over medium heat. Add chopped bacon and sauté until browned and slightly crispy. Remove from the pan and set aside.

Step 3
In the same pan, add diced onion and cook until softened, about 3 minutes. Add garlic and stir for another 30 seconds until fragrant.

Step 4
Add the chopped kimchi to the pan, cooking for 3–4 minutes to deepen its flavor. Stir in gochujang, soy sauce, sugar, and the reserved kimchi juice. Mix well to create a spicy, umami-rich base.

Step 5
Toss in the shredded carrots or diced bell peppers and cook for another 2 minutes. Then return the cooked bacon to the pan and stir everything together.

Step 6
Add the cold rice to the pan. Break it up with a spatula, mixing thoroughly to coat every grain in the spicy kimchi mixture. Stir in sliced green onions, reserving some for garnish. Season with salt and pepper to taste.

Step 7
Turn off the heat and let the mixture cool slightly. In a small bowl, beat the eggs and pour them into the rice mixture. Stir quickly to combine, ensuring the eggs coat the rice evenly without scrambling.

Step 8
Transfer the rice mixture into the prepared baking dish, pressing it gently into an even layer. Sprinkle shredded cheese over the top if using, or leave it bare for a more traditional take.

Step 9
Bake uncovered for 30 to 35 minutes, or until the casserole is heated through and the top is golden and slightly crisp around the edges.

Step 10
Remove from the oven and let it rest for 5–10 minutes. Garnish with reserved green onions and toasted sesame seeds before serving.