Pastry Face is a superhero identity of Lisa Simpson.
Pastry Face was the name of a member of The League of Superheroes. He died when he drowned in a vat of bundt cake batter.
When investigating pranks happening in Springfield, which were taking place around a bake-off, Lisa took on the mantle of Pastry Face. Pastry Face started by warning Krusty not to be a judge at the Springfield/Shelbyville bake-off. Pastry Face then got help from former members of The League of Superheroes and other heroes in Springfield. Pastry Face later broke into the Simpson house to reveal that she knew that Pie Man and Cupcake Kid were Homer and Bart. When Pie Man, Pastry Face and Cupcake Kid were pantsed by Jimbo, Dolph, and Kearney, Homer and Bart learned that Pastry Face was Lisa.
Pastry Face later figured out that Bart was behind all the pranks. She and the other heroes all confronted Bart together.