Castellanas lentils originate from Salamanca and are characterized as the largest in the lentil group, measuring between 7 and 9 millimeters. These legumes are light green but may darken over time, with some grains known as 'avinadas lentils.' Their shape is broad, rounded, and flat, making them distinctive. These lentils have a very thin skin and are recognized for their tenderness and mild taste, making them ideal for various dishes. They cook excellently in any type of water, facilitating preparation.