Soak the rice cakes in water to soften them.
Cut the fish cakes and green onions into bite-sized pieces.
Pour water into a pot and bring to a boil.
Make the sauce by mixing gochujang, gochugaru, sugar, soy sauce, and minced garlic.
Add the rice cakes, fish cakes, and sauce into the boiling water and simmer over medium heat.
Stir well, then add the green onions and simmer over low heat until thickened.
Once the rice cakes become soft and the sauce thickens, it's ready to serve.