The stall with rock cakes.
A Rock cake is something of an ogre delicacy and is quite literally a cake made out of rock. Rock cakes can be obtained by stealing from the market stall in the ogre town of Gu'Tanoth, granting 6.5 Thieving experience.
A rock cake is required as a bribe in order to access the central parts of the Gu'Tanoth, which is necessary during the Watchtower quest. The player must give a rock cake to a guard in order to be allowed to climb over a rampart that blocks the way to a rope bridge.
Players often eat rock cakes while using Dharok's to lower their Constitution so they can hit higher. Eating it will hurt players for 40 life points; however, if they already have very low lifepoints (30/800 for example), the cake will start to cause 0 life points. High leveled players with Dharok's often yell out, "Ow! I nearly broke a tooth!" during Pest Control after eating a rock cake.
According to Easta Buni, rock cakes are a "speshul Easta fud."
Trivia
- The rock cake is a play on the real world rock cake, which is a small cake with a rough surface containing raisins and currants.
- The rock cake could be reference to the Harry Potter series, in which Hagrid offers Harry a rock cake, upon which Harry nearly breaks a tooth.