In Harry Potter 6 ds game where do you find the cauldron cakes?

The Cauldron Cakes are found in Hogwarts Castle, specifically in the Potions Classroom. They are placed on a table near the cauldron where you brew the Antidote to the Poison Potion.

To access the Potions Classroom, you will need to complete the "The Potion Master" quest.

I hope this helps you find the delicious Cauldron Cakes!