Rich in fiber, protein, and iron, beans form the basis of many diets around the world, particularly for vegetarians. There are two main types of cultivated beans – New World and Old World. New World beans are all in the genus Phaseolus and are known commonly as black, pinto, lima, and kidney among many others. Old World beans are represented by a number of genera – Vigna (azuki, mung), Cicer (chickpea), Pisum (pea), Lens (lentil), and Glycine (soy).
Although the wide variety of beans we see today were cultivated at different times and regions, they are all members of the family Fabaceae and thus share many common traits. Perhaps most importantly, beans have a symbiotic relationship with nitrogen-fixing bacteria. This means that the bacteria provide the plants with a necessary nutrient that is often hard to come by – nitrogen.
Use this method for cooking almost any variety of dried beans. Quick cooking varieties, like lentils, won’t hold up very well and should be cooked on the stovetop instead.
Start with any amount of beans you like. The upper limit is that they need to fit in your slow cooker along with the cooking liquid. The lower limit is that you should make enough to last you through a few recipes. Rinse the dried beans with cold water, drain, and place in the crock of your slow cooker. Cover with cold water by about an inch. I usually measure to the first crease in my index finger. Add in a large pinch of salt. Cover, turn the slow cooker to high, and go about your business!
Depending on the bean, the cooking time may take several hours. Chickpeas (pictured here) take longer than black or pinto. I start checking after the first hour, adding more water or salt as needed. The beans need to be below the water surface at all times. If the water runs low, add in enough hot water to cover them again. Start tasting after a couple hours and add more salt as needed. There is a lot of wiggle room in this method. If you slightly undercook them, you can still use them in salads or finish off the cooking in another recipe. If you slightly overcook them, they make for a good pâté. Think hummus, refried beans, or homemade veggie burgers.
Leftover cooked beans can be refrigerated for about a week or frozen for a couple months. Store them in their cooking liquid. Chickpeas, however, should be drained and rinsed before being frozen.