Rinse yuca well. If the waxy coating makes it hard to handle, scrub and rinse under warm water to remove most of the wax. Use your largest, sharpest knife to cut yucas into sections 2- to 3-inches long. On each section, make one slice through the tough “bark” and pinkish inner skin. Use paring knife to lift up and peel off the skin layers to reveal snowy white flesh underneath. Once you get it started, the skin layers slip away with surprising ease. Do not eat it raw. Cooking makes the low levels of cyanogenic glucosides safe.