Cut the rice cakes and fish cakes into bite-sized pieces.
In a pan, add water, gochujang (Korean chili paste), gochugaru (Korean chili flakes), sugar, and soy sauce, then bring to a boil.
Once the sauce boils, add the rice cakes and fish cakes, then stir-fry on medium heat for 7 minutes.
Slice the green onion and add it in, then simmer for 2 more minutes.