this book maybe becomes a little repetitive. and some of the ratios are less fundamental than others. but it will change the way you look at recipes and your approach to cooking in general. the point is that it is the ratios of ingredients which are important. which change the nature of what it is you are cooking. an eye opener, and approach-changer, especially for pastry and baking.
Ruhlman, Michael., Ratio: The Simple Codes Behind the Craft of Cooking