This frozen dessert is impressive not only in how quickly and easily it comes together but also in how elegant the speckled, mosaic-like slices look when plated. The semifreddo is rich yet light in flavor, with both creaminess and crunch, and it can be made well in advance. Fresh or frozen (thawed) pitted sweet cherries work equally well. We roughly chop the cherries, then briefly steep them in amaretto or kirsch (balsamic vinegar is excellent, too), plus almond or vanilla extract. Thin, snappy-crisp chocolate cookies are the type to use here. We especially liked Tate’s Bake Shop double chocolate chip cookies. If you like, serve the slices with chocolate sauce. To make it easy to get the semifreddo out of the pan, we line it with plastic wrap. Sprinkling the pan with water keeps the plastic in place.