On the Mezzanine, you'll encounter the ghostly Chef Soulfflé. He's guarding an elevator button and won't give it up easily. To defeat him, you'll need to use the food items in the kitchen. Stun him with your Strobulb, then use the Suction Shot to grab a nearby food item (like a watermelon) and launch it at him. Repeat this process, dodging his cleaver attacks, until he's defeated and drops the elevator button.
