The ideal temperature for dehydrating mushrooms is around 125 degrees F (or 52 C) . Here are the steps to dehydrate mushrooms:

1. Clean and slice the mushrooms.
2. Place the mushroom slices in a single layer on the dehydrator trays.
3. Dehydrate at 125 F (52 C) for 3-8 hours until the mushrooms are brittle and break easily.
4. If your dehydrator doesnt have a temperature control, you can still use it to dry mushrooms. Dehydrate at the highest temperature setting and check the mushrooms every hour or so until they are completely dry.
5. If youre using an oven, set it to the lowest temperature setting and dry the mushrooms on a lined baking sheet. Flip the pieces over every hour and remove them as soon as they are completely dry.

Remember to let the mushrooms cool completely before storing them in an airtight container. If you notice any moisture or condensation forming on the sides of the container, put the mushrooms back into the dehydrator to dry for longer.