How do you do sorbetis chilly reception on super mario galaxy 2?

To complete the "Sorbetti's Chilly Reception" mission in Super Mario Galaxy 2, you need to navigate to the Chill Penguin planet in the World 4 - Freezy Flake Galaxy. Once there, you'll encounter Sorbetti, who requires you to defeat a series of Ice Piranha Plants. Use your Spin attack to defeat them, and then collect the Power Star that appears after you defeat the last one. Remember to avoid the cold water and icy obstacles while making your way to the plants!