Preboiled Black Rajma refers to black kidney beans (a darker variety of rajma) that have been preboiled or partially cooked, making them a convenient and time-saving ingredient for preparing a variety of dishes. Similar to traditional rajma (red kidney beans), black rajma is rich in protein, fiber, iron, and other essential nutrients. Using preboiled black rajma significantly cuts down on cooking time since the beans are already cooked and tender, allowing you to focus on flavoring and serving your dish.