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Hold a bundle of stalks under a stream of cool, running water. Use your fingertips to lightly scrub away any dirt and debris clinging to the stalks. Shake off the excess water, then pat the scapes dry with a clean paper towel.  If you’re washing a lot of scapes at once, it may be easiest to do it in a colander. Don’t attempt to clean scapes by soaking them. This can cause them to absorb too much water, diluting their flavor and leaving them mushy. A cutting board or mat is essential for protecting your countertops, since you’ll be making a lot of quick cuts. Because of the way scapes curl, and the fact that they tend to vary in size, it’s recommended that you cut them one at a time. Cut away the tip of the scape just below the bulbous white neck. Do the same for the lower end of the stalk where it starts to become hard and woody. Toss both sections in the trash, or add them to your compost heap. You should be left with just the smooth, light green shaft. The top and bottom portions of the scape are tough and chewy, so it’s best to just throw them away. Move the blade of your knife up and down along the length of the stalks with a smooth lever action, holding them steady with your free hand. It may be necessary to stop and reposition especially curved stalks as you go. Once sliced, your scapes will lend a burst of aromatic flavor to savory dishes in much the same way as scallions, leeks, or chives.  The exact thickness of each slice will depend on your knife-handling skills and your intended use for the scapes. Toss a handful of sliced scapes into a stir fry or sauté, or sprinkle them onto a salad or loaded baked potato. They also go well in sauces and dips like salsa verde, guacamole, chimichurri, and pesto. Instead of aiming for a fine slice, cut the stalks into 1-2 inch (2.5-5 cm) sections roughly the same size as broken green beans. In this form, they’ll be perfect for adding a deep, savory note to soups, stews, and marinades.  If you don’t intend to eat the scapes, leave the stalks a little longer so they’ll be easy to pick out of the pot or pan once you’re done cooking. Try adding chopped scapes to a vegetable medley, or steaming them and serving them on their own. When cooked, they have a crunchy texture not unlike asparagus, with a mild onion flavor.

Summary:
Wash the scapes thoroughly. Place the scapes on a cutting board. Trim the ends off the stalk. Cut the scapes into thin slices. Leave the scapes in larger pieces for more flavorful cooking.