I have just bought a home with a built-in microwave oven that has a turntable. I want to microwave a large pyrex rectangular pan but can't because the turntable prevents this. The microwave mfg (Kitchen Aid) says not to use the microwave oven without the turnable in place. Cannot find a microwave accessory to solve this problem. (Was thinking of some sort of a raised shelf or platform) Does anyone have a solution?