Plastic wrap and tinfoil make fickle guardians for frosted sheet cakes and potluck brownies. Nordic Ware’s Half Sheet Cover ($8) snaps on tightly to keep food fresh and make delivery to your event easy. These trustworthy covers are sold separately or with the baking sheet as a set. Now jelly rolls and profiteroles can be stored and transported in the same pan they were made in. Available at Kitchen Outfitters, Acton Woods Plaza, 342 Great Road, Acton, 978-263-1955, or www.amazon.com. VALERIE RYAN