Make vegetable broth w/ bouillon cubes. Soak the rice cakes for about 20 minutes if hardened or refrigerated. Cut the cabbage and scallions into about 2-inch long pieces.

Add the broth to a large pan. Stir in the sauce ingredients. Bring it to a boil over medium high heat, stirring to dissolve the red chili pepper paste (gochujang).

Add the rice cakes. Boil until the rice cakes become very soft and the sauce is thickened, about 8 - 10 minutes. Stir frequently so the rice cakes don't stick to the bottom of the pan.

Add the vegetables. Continue to boil, stirring constantly, for an additional 4 - 6 minutes. Depending on rice cakes, you may need more time to reach a desired level of softness. Add more broth or water as necessary. Taste the sauce, and adjust the seasoning if needed. Serve immediately.