The International Journal of Food Sciences and Nutrition published a study to explore the effect of different cooking methods on the nutritional value and antioxidant activity of cultivated mushrooms.

You can see a summary here.
(Please Note: To read the full report you will have to pay.)

The Two Best Ways to Cook Mushrooms:

  1. Microwave them
  2. Grill them

The BBC have given their summary of the study in the Health section of their website. 

We are pleased to see mushrooms being promoted in this way. They really are great for nutrition.

Check out all the nutritional benefits of mushrooms here.