The beans expand in size while being rinsed, and again during cooking. One cup of dried beans yields about three cups cooked; one pound of dried beans yields approximately six cups cooked.
Spread the dried red kidney beans out onto a clean baking sheet. Sift through them with your hands to remove any dirt, small pebbles or other debris. Transfer the beans to a colander and rinse them under cold running water.
Place the rinsed beans into a large stock pot. Add 3 cups cold water for every 1 cup of beans, or about 10 cups of water for a 1-pound package. Let the beans soak overnight, uncovered.
Drain the water from the beans by pouring the contents of the pot through a colander. Rinse them under cold running water and then return them to the pot. Cover the beans with fresh water—again, 3 cups cold water for every 1 cup of beans, or about 10 cups water for a 1-pound package —and place on the stove.
Bring the beans and water to a rolling boil over medium-high heat. Reduce the heat to medium-low and simmer for approximately 2 hours. Remove one of the beans to check for doneness by biting or pinching.
Continue simmering the beans for another 15 minutes, if necessary. Check again for softness and repeat every 15 minutes until the desired tenderness is reached.
Remove the red kidney beans from the heat, add salt and pepper to taste and serve immediately. Store any leftovers, covered, in the refrigerator for up to four days.