Etsko Kizawa has a passion: to educate New Yorkers on the virtues of Japanese home cooking, in all its soyful glory. Try her miso soup full of vegetables or a plate of nikujaga, a beef-and-potato stew. Specialties include a deep-fried tofu Treasure Sack stuffed with vegetables, and the seaweed salad with carrots and shiitake mushrooms. Chocolate- red-bean-or green-tea-tofu pudding goes down smooth as silk. If you can"t score a table in the sparely decorated storefront, get a fresh fruit soy smoothie to go.