DIAGNOSIS The ceiling of the cooking chamber, where the heating element is housed, collects grease aerosol. It's designed to be cleaned, but carefully, to avoid damaging the element.
FIX Unplug and let the unit cool completely. Fill the basket with hot, soapy water. Place the basket back into the unit and let the steam from the water soften the grease for 10-15 minutes. Use a soft-bristled brush (like a dish brush or a dedicated grill brush) to gently scrub the ceiling and the heating element guard. Wipe out with a damp cloth.
IF THAT DIDN'T WORK For stubborn, baked-on grease, make a paste of baking soda and water. Apply it to the greasy areas (avoiding direct contact with the heating element coil itself). Let it sit for 20 minutes, then scrub gently with the soft brush and wipe clean.
HEADS UP Never immerse the main unit in water or run water directly into the top vent. Do not use metal scouring pads or abrasive cleaners on the non-stick interior or the heating element, as you can cause scratches or damage the coating.