Reading a cookbook from cover to cover usually isn't something that strikes me as something I want to do. Michael Ruhlman's Ratio, however, is different from any other cookbook. It is Ruhlman's explanations on how a large number of things can be made in the kitchen based on following simple ratios (by weight). For example, if you want to make a vinaigrette it's three parts oil to one of vinegar. Simple, huh? If you want to add herbs to it, you can, but the basic ratio is 3:1. Remember that ratio and you don't need to ever look it up in a cookbook.
Ratio is filled with tons of things like that. Unfortunately, most of the recipes aren't all that good for you. Lots of doughs and cakes and pastry recipes. Lots of sauces. But if you moderate yourself, it is pretty fascinating all the neat things that can be done with these simple ratios.
The other caveat to the book is that there are a lot of exceptions to the rules. Ruhlman will start off explaining a ratio and then talk about how ideally, you probably want to tinker with it. So even once you learn the ratio, you might not actually want to use it which is a bit annoying but then again, part of cooking is creativity and you should probably be tinkering with the ratio on your own.
Ultimately, I liked the book a lot and have used it considerably. It was almost worth the cost just to be able to make single serving pancakes. My youngest son is the only one in the household that likes pancakes and it used to be a pain to have to whip up a large bowl of batter for one or two cakes and then refrigerate the rest. No more. Also, Ruhlman is a really good writer and makes the act of mixing things together interesting. I probably learned more about cooking from this book than any other source I can think of.