They look like Krabby Patties, except they contain Plankton's chum in them. The meat looks like a multi-colored organ and the chum is different from others. Only the monster is able to consume the Chum Patty.
Role in episode
They appear in the scene with the giant abyss monster. The chum came from Chum Charges, which Plankton used to destroy the submarine. It punches holes through the wall and chum starts to go into the submarine. One of them lands on a bun. The monster, while still in anger for more food, takes a look inside for food. He then sees this food and asks if he can try it. SpongeBob and Patrick then give it to him.
The monster likes it and he asks for more. They start to make more until the sea monster is stuffed.
Role in SpongeBob Moves In!
They appear as a cooking ingredient. However, unlike the Chum Patty shown in the series, the Chum Patties in the game are literal patties made of chum.