In a medium pot, combine 4 cups of anchovy stock or water with a piece of dried kelp. Bring the mixture to a boil over medium-high heat, then reduce the heat to low. Remove the kelp after 5 minutes, allowing the broth to simmer uncovered for 10 minutes.

Vigorously stir in 3 tablespoons of gochujang, 1 tablespoon of gochugaru, 2 tablespoons of soy sauce, and 1 tablespoon of sugar into the simmering broth. Increase the heat back to medium and let this mixture boil for about 2 minutes.

Add 1 pound of tteokbokki (Korean rice cakes), stirring well to coat them in the spicy broth. Cook for 8 to 10 minutes, stirring frequently.

Incorporate 1 cup of rinsed and sliced Korean fish cakes into the pot with the rice cakes. Continue cooking for an additional 4 minutes, stirring continuously.

Turn off the heat and mix in 1 tablespoon of toasted sesame oil and chopped scallions for added freshness. Transfer to a serving bowl and sprinkle with sesame seeds for garnish.