A really great way to cut calories in a number of baking recipes is to substitute in a 1:1 ratio of fat-free plain yogurt for butter or vegetable oil . The yogurt provides moisture and added nutrition while allowing for the complete removal of butter from a recipe. Applesauce can also be used in the place of butter or oil in a 1:1 ratio for many baking situations. The applesauce also adds moisture to the recipe as well as fiber and vitamins while allowing for the complete omission of fat from the recipe. One last option for omitting butter from a baked good recipe is to use half fat-free yogurt and half applesauce in place of the butter (in the same amount as the called-for fat). Both of these substitutions are ideal for quick bread and muffin recipes, and even brownie recipes, but are not necessarily ideal for all baked goods. For example, shortbread would not be a good place for the substitution, as the flakiness of the shortbread is created with butter. One last important note: yogurt and/or applesauce can not be substituted for butter, oil, or cooking spray to keep baked goods from sticking to the pan, this requires grease.
***You should not cook with flavored sugar-free yogurt that contains aspartame or NutraSweet, as the sweetener may change flavor when exposed to heat***