Tofu is the foundation of many a delicious vegetarian meal, including this one. For best results, always drain the block of tofu before using by placing it between layers of paper towels and pressing with a pan or other heavy object, changing the towels as needed. This is especially helpful when frying the tofu so you can get a nice browned surface. Here the tofu is served in endive leaves with a sauce that's made by blending watercress with chives.