It is normal for your burner tray to tarnish during regular operation. The surface tarnish on the stainless-steel appears as a rusty-dark brown and gold-yellow color (it is not rust!). The tarnish is caused by the heat of the flame and can be removed by using standard stainless-steel cleaning products (we recommend a product called “Barkeeper’s Friend”). Use a non-abrasive pad to wipe in the direction of the grain of the stainless-steel (do not wipe in a circular motion, or against the grain, or scratches may appear). With a little ‘elbow grease’, the surface tarnish can be removed.