Instead of Cheddar, stuff these mushrooms with your favorite cheese; try crumbled blue cheese, feta or shredded Swiss.
Wash sand or soil off the mushrooms by swishing them briefly in a large bowl of cool water. Lift them out and transfer them to another bowl. Repeat two more times with fresh water. Do not dump the bowl of mushrooms into a colander; sand from the bottom of the bowl will end up on top of the mushrooms. Gently dry mushrooms with a paper towel.
Stuff the mushrooms one day ahead of serving time, cover and refrigerate until ready to bake.