If you do not already have them, go to the Culinaromancer's chest and buy an egg, a bucket of milk, a pot of flour, and a cake tin. The quickest way to get to the Wizards Tower is to use the Teleport option from the Wicked Hood. Speak to Traiborn on the floor[help] of the Wizard's Tower, and ask about helping the Lumbridge Sage. He will tell you that you need to enchant all the ingredients for a normal cake: an egg, a bucket of milk, and some flour.