Not crazy about "cooking" with fabric. I do use the bowl cozies to heat up stuff all the time and I love it. Yes, I put the cozie in the microwave, the purpose of the cozie is to prevent burning fingers. If you have to take a hot bowl out of the microwave and place into a cozie, that defeats the purpose. Never more than 2 minutes at a time, if not heated enough, 2 more minutes