Saute veggies: Add oil to a wok or large fry pan over medium-high heat. Once hot, add onion and cook for 2 minutes. Add garlic and sauté for 30 seconds. Add chopped kimchi and toss for 1 minute.

Add rice: Separate the cold, cooked rice grains with your fingers and add to the pan. Toss gently to combine.

Season: Add soy sauce, sesame oil, black pepper, and 1 chopped green onion. Toss gently to combine (you don't want to over-stir the rice and make it mushy). Taste and add pepper, salt or more soy sauce, as needed.

Serve immediately, with gochujang hot sauce, if desired.