 How to Clean Leaks In the event that you know what a leak is and actually happen to have one, here's how to clean it. You will need Leaks Sharp knife Cutting board Sink Paper towels Optional A medium bowl Step 1 Pull off the tough outer leaves of the leak Step 2 Grasp the knife in your dominant hand holding the handle close to the blade with three fingers, middle, ring and pinky. Curl your forefinger around one side of the blade while holding your thumb on the opposite side. Step 3 With your non-knife-wielding hand hold the leak firmly on the cutting board close to the area you will cut. Step 4 Cut off the top dark green part of the leak and discard. You only use the white and very light green part of the leak. For recipes that require whole leaks, cut off one quarter inch from the root end and slice the leak in half lengthwise. Step 5 Leaks can be very sandy. Hold the leak halves under running water to remove the dirt. Gently pull apart the layers to remove hidden dirt and sand. If you prefer to leave the leaks whole, slice through the leaks lengthwise but do not cut all the way through or they will fall apart. Gently open the leak under running water to thoroughly remove all the dirt. Step 6 For recipes that require rounds of leak, slice a half an inch from the bottom and discard. Chop the leaks in rounds and submerge the pieces in a sink or bowl of water. Gently pry the layers to let water get between them but don't pull them apart completely. Step 7 Dry the whole, half or sliced leak round on a paper towel. Start cooking. Did you know the leak has been the national symbol of whale since the 6th century when Welsh warriors wore them on their helmets to identify each other from their enemies.