This is a combination of all the questions I've been asked about this terrific, but evidently hard-to-find product, many times.

First, they are just that --- flakes of dehydrated beans, easily reconstituted with boiling water. The best varieties feature only beans and sea salt, no seasonings. You pour the water over them, let them set 10 minutes, and voila --- you have a thick and delicious, smooth, satisfying puree of beans, like refried beans, only without all the fat. We are talking fresh burritos, enchiladas, or side dishes mucho FAST here. Also, you can add the beans to a simmering vegetable soup, and they thicken it in a really special way, adding body as well as flavor and protein (to say nothing of the health-giving benefits of beans, which are legion). However, if you want whole beans, either cook them from scratch or open a can.

My favorite brand is called Taste Adventure, and they make both a black bean and a pinto bean. If you want to mail order them, go to www.tasteadventure.com. You do have to buy in quantity, but many readers have gone ahead and done just that, and written me that they were quite happy with the product and found it wholly worth it. Taste Adventure also makes a quite good instant split pea soup --- take it on a plane, rehydrate with boiling water (the flight attendants have it on the beverage cart, for tea)  and you will be the envy of your seatmates. This points up another advantage of dehydration: the beans are not only almost ready to eat, but they are light and easily transportable --- terrific backpacking food if you like to camp out.