Possible Clues:

• Cook corn without oil
• Prepare sans oil, as a movie treat
• Heat without oil at a movie theater, say
• Make a corny snack without using oil
• Prepare, as a certain movie snack
• Cook without oil, as kernels
• Prepare without oil, in a way
• Cook without oil, as some corn
• Cook corn, in a way
• Cook kernels, one way