Yes, you can bake cakes directly on an oven tray, but it's typically better to use some form of grease or lining to prevent the cake from sticking and to ensure even baking. There are a few options for lining your oven tray:
Greased and Floured Tray: You can grease the oven tray with butter or oil and then dust it with flour. This creates a non-stick surface and helps the cake release easily after baking.
Parchment Paper: Lining the tray with parchment paper is a common method. It provides a non-stick surface, and the cake can be easily lifted off the tray once it's done baking.
Baking Paper/Foil: Similar to parchment paper, using baking paper or aluminum foil can also help prevent sticking and make cleanup easier.
Using one of these methods is especially important for delicate cakes that might be more prone to sticking or if you're baking a cake that doesn't contain a lot of fat (like oil or butter) in the batter, which makes it more likely to adhere to the tray.
Remember to preheat your oven to the recommended temperature before baking and to follow the specific instructions in your cake recipe for the best results.