I've made macarons before but the results have not been consistent. Even within the same batch, some are perfect (i.e., have smooth domed top and feet) while others are wrinkled on top with no feet. The imperfect macarons taste great too but it would be nice to get both taste, texture and appearance right.
I found blogs that swear by the use of Italian meringue. I'm going to give this a try, but first, do I really need to stack together several sheets to prevent too much heat on the bottom? Is it all right to use an air-insulated cookie sheet instead? My sheet pans don't nestle snugly together so I'm not sure they'll stack up ok.