Soak the grates: Fill the sink with hot water, and add enough grease-cutting soap to create suds. Allow the grates to soak for about 15 minutes to allow the soap to cut through the remaining grease. Drain the water from the sink.
Clean the grates: Place a non-abrasive cleanser onto a nylon scrubbing pad. Scrub at the grates with the powder to remove any remaining grease or food particles. Rinse the grates with warm water, and apply the powder to any section where debris remains. Allow the powder to sit for five minutes, scrub it off, and rinse the grates again. Dry the grates off completely with a dry paper towel before placing them back on the stove.