- "The rock cakes almost broke their teeth."
- — Harry's and Ron's opinion on Hagrid's rock cakes[src]
Rock cakes are a type of fruitcakes. They are supposed to have a hard surface, but not be quite as rocky as Hagrid's version seemed to. Eating one of Hagrid's rock cakes was exactly like eating a rock, as they were so hard that they could break teeth instead of being a lovely treat.
Ron Weasley, Hermione Granger, and Harry Potter forced themselves to eat a few of these whenever they visited Rubeus Hagrid. Although they complained about the rock cakes' hardness, stickiness, and tastelessness, they never had the heart to tell Hagrid this, as it would have hurt his feelings. He served ones that contained raisins to Harry and Ron for the first time after their first week of lessons in 1991.
When Harry, Ron and Hermione visited Hagrid in the 1996-1997 school year for the first time that year at his hut, Hagrid presented them with a plate of rock cakes and tea. Harry was hungry enough that he took one of the cakes at once, but he later abandoned it "after an ominous cracking noise from one of his back teeth."
- Harry Potter and the Philosopher's Stone (First appearance)
- Harry Potter and the Goblet of Fire
- Harry Potter and the Half-Blood Prince
- Harry Potter and the Deathly Hallows (Mentioned only)
- The Wizarding World of Harry Potter
- Harry Potter: Hogwarts Mystery (Mentioned only)