It's almost that time of year again-holiday pies, cookies, cakes, and breads are right around the corner. But as fun as baking can be, it can also shake the confidence of the most steely-nerved cook. Once your biscuits, pie, or cheesecake is in the oven (or, rather, in the pan), all bets are off. Why? Baking is essentially chemistry. Success doesn't just depend on the right mix of ingredients; it also relies on proportion, mixing method, and temperature-all of which need to work in harmony to produce a perfect tall and fluffy biscuit, a handsome loaf of fine-crumbed pound cake, or a plate of thick and chewy chocolate chip cookies.