This book taught me that a few ingredients can make an awesome dinner. Some favorites: gougères (cheesy puff balls), steak frites (my default steak topping is now shallot and thyme), and Atlantic salmon with leeks (pan fried...no need to flip...how easy is that?).
3. Maxime Bilet and Nathan Myhrvold's Modernist Cuisine at Home
This book helped me understand the science behind cooking. And that knowledge made me a better cook. Now I *think* about what a technique is trying to accomplish instead of blindly following a recipe. I also use a blowtorch more often.