Cooks at high altitude usually have a culinary war story or two about the cake that never rose, the cookies that came out flat or the beans that never cooked through. In a sky-high kitchen, making dried black beans in a slow cooker might seem to take eons or never yield an edible dish at all. With a few simple adjustments, preparing dried black beans in a slow cooker will no longer be a guessing game. For the best results, use recently purchased beans. The older the bean, the longer it will take to cook -- especially at altitude.
Prepping Your Beans
Sort beans to scan for and remove foreign objects, such as small twigs or stones. Rinse beans in a colander.
Place dried beans in a bowl and cover with cold water, about 4 cups of water for every 1 cup of beans. Let stand uncovered for 8 to 10 hours or overnight.
Use an alternative soaking option if you're short on time. Boil water and beans for 2 minutes, remove from heat, cover and soak for 2 to 3 hours.
Drain water from the bowl of soaked beans. Rinse off beans in a colander.
Quality Slow Cooker Time
Add soaked black beans to the slow cooker along with enough water to cover the beans by approximately 2 to 3 inches. At high altitude, the boiling point of liquid drops by 1 degree for every 500-foot increase in elevation, so to maintain liquid just above a simmer, use either the medium setting or 200 degrees Fahrenheit, if your slow cooker has temperature controls. Monitor your beans to ensure the liquid is just above a simmer, with small active bubbles.
Add salt or any acidic ingredients, like vinegar or citrus juice, after your beans have simmered for at least 2 hours. Usually, a recipe for 2 cups of beans will require three-quarters to 2 teaspoons of salt. Incorporating salt or acid too early might affect the ability of the liquid to soften the beans.
Simmer beans for 8 to 12 hours in the slow cooker until tender. The higher the elevation, the longer the beans will take.