Ann Byrn is on to something. Her first book, The Cake Mix Doctor, showed readers how to tweak store-bought cake mixes to produce "like-homemade" treats. The sequel, Chocolate from the Cake Mix Doctor repeats Byrn"s foolproof approach, focusing solely on chocolate. The strategy? Begin with commercial mixes like chocolate cake, devil"s food, and chocolate brownie; alter them with ingredients that add flavor, such as cocoa powder, or richness and moistness, like sour cream; use homemade frostings (supermarket versions won"t cut it); and you"re in business. "My mission," says Byrn, "is to help busy cooks find the time to bake even when company is not coming." If her sweets lack true homemade quality, they nonetheless produce entirely creditable desserts most bakers, and those they feed, will applaud. Beginning with a blueprint for mix-doctoring success, which includes information on pantry essentials and a useful chocolate primer, the book then presents over 150 easy recipes for a full range of chocolate layer, pound, sheet, angel food, and chiffon cakes, as well as muffins, cookies, brownies, and more. Among these, readers will surely want to try Triple Decker Raspberry Chocolate Cake, White Chocolate Peach Cake, Frozen Chocolate Neapolitan Cake, and Jessica"s Caramel Chocolate Brownies. Besides more basic finishes, the frosting chapter offers recipes for the likes of Crushed Peppermint Buttercream Frosting. An introductory section presents color photos of all the cakes; Byrn also supplies interesting technical information, lore (Nuggets of Chocolate History, for one), and a chocolate cake glossary all bakers can use. --Arthur Boehm