A cracked cooking urn is the resulting urn after the player starts filling a cracked cooking urn (empty). While the player carries the urn in their backpack, it will fill up passively as the player cooks food requiring up to and including level 10 Cooking, until it is filled with 2,000 experience and becomes a cracked cooking urn (full).
The fully filled urn will grant 400 Cooking experience after teleporting the urn to Ernie. While carrying an urn enhancer, it will instead grant 500 experience per teleported urn for a cost of 20 charges.
Making the urns and adding a fire rune to the urns requires level 1 Crafting. The Assist System and temporary skill boost can be used to do so. Filling the urns and teleporting the urns does not require a Crafting level.