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How to clean a microwave with baking soda
Remove the turntable and support ring, and sprinkle baking soda.
Set these pieces aside, on the kitchen counter or in the sink. Sprinkle the baking soda across the bottom of the microwave.
Alternatively, you can use a baking soda paste to clean your microwave. Mix two parts baking soda to one part water and use a butter knife to apply the paste to the inside of the microwave.