I prepared these on the grill and they were fabulous! Grill sausage patty on one side, flip. Place mushroom cap, like a lid, over the cooked side of the patty. When the second side of the patty is cooked, turn the entire thing to grill the mushroom cap. (The now cooked sausage patty will be nestled inside and staying warm) Cover with slice of cheese. When cheese is melted, remove to plate and top with onions. Wow, like serving a steak! We added grilled asparagus and a salad.