Rinse and pick over beans
Contaminated seeds are usually the source of sprout-related illness outbreaks, so getting clean seeds is essential. Choose whole (split red lentils, for example, won’t work) and untreated beans that are meant for sprouting or eating. Reputable health food stores and online catalogs (such as sproutpeople.org and sproutman.com) are your best bet. The ones sold in gardening packets are likely to be chemically treated and should not be used for sprouting.
Wash them and remove any damaged beans and foreign objects.
Place beans in jar with water
Soak the beans for 8-12 hours at room temperature. A general rule of thumb: the larger the bean, the longer the soak.
Rinse and drain
Keep doing this until the sprouts grow to the length you want. Lentils and mung beans have been the fastest-growing in my experience – they just take a day or two after the initial soak. The whole process can take anywhere from 2 – 5 days. These lentils are just about done.
Let alfalfa sprouts grow to about an inch. Mung bean, lentil, chickpea and adzuki sprouts are good at around a half-inch, but it’s a matter of preference.
Final step for alfalfa
Wash and eat!
These sprouts are commonly eaten raw, but with the exception of alfalfa sprouts (which would turn to mush if cooked), other sprouted beans can withstand the heat. Mung bean sprouts can be added into a dish in the final two minutes of cooking. Sprouted lentils are fully cooked after 4-5 minutes of steaming. Sprouted chickpeas and adzuki beans need around 15 minutes of cooking.