2 Make cookies the same size and shape for even baking and browning.
3 Use rimless baking sheets with slightly slanted lips so that heat can circulate around cookies. Rimmed sheets are less suitable, but if they are all you have in your cupboard, use them. You can turn them over and use the flat bottoms. Heavy, shiny sheets are best. They bake cookies evenly, prevent bottoms from browning too quickly and do not warp.
4 Line baking sheets with parchment paper, silicone baking liners, nonstick foil or prepare as directed in recipe.
5 Bake one sheet at a time on rack positioned in centre of oven. However, to bake more than one sheet of cookies at a time, position racks in top and bottom thirds of oven and rotate sheets from top to bottom and from front to back halfway through baking time.
6 If you have only one or two baking sheets, let the sheets cool completely between baking the batches. Hot baking sheets will melt cookie dough, resulting in changes to the texture and shape of cookies.
7 Always check cookies for doneness at the earliest time called for.
8 Let cookies cool completely on rack to prevent soggy bottoms.
9 Store crisp and soft cookies separately in airtight containers.
Excerpted from Canadian Living The Complete Christmas Book by the editors of Canadian Living Magazine Copyright © 2007 by the editors of Canadian Living Magazine. Excerpted by permission of Transcontinental Books, a division of Random House of Canada Limited. All rights reserved. No part of this excerpt may be reproduced or reprinted without permission in writing from the publisher.