Onion rings are a guilty pleasure. This recipe eliminates the guilt and the rings are sheer pleasure! I love onion rings but always feel so full after indulging and then very guilty for ingesting all the grease and fat. I happened to see Rocco DiSpirito make these onion rings on the Rachel Ray TV show. They are baked, not fried. The onion rings are soaked in buttermilk, dredged in flour, dipped in frothy egg whites and then coated in panko crumbs. A spritz of cooking spray before popping them into a hot oven ensures a very crispy coating on a tender, sweet onion. You won't miss the grease one bit. The smoky mayonnaise is a yummy compliment to the crunchy rings.