Soak the rice cakes in water for 10 minutes.
Cut the fish cake, onion, and green onion into bite-sized pieces.
In a pot, bring 300ml of water to a boil with gochujang (Korean chili paste), gochugaru (Korean chili flakes), sugar, and soy sauce.
Once the sauce starts boiling, add the rice cakes, fish cake, and onion. Cook for 5 minutes.
Add green onion and minced garlic, and simmer for another 3 minutes.