Making chocolate curls is a simple 2-ingredient recipe. Here is the basic process: Melt chocolate with shortening. Spread thinly on the back of a smooth baking sheet. Place in the freezer. After just 2-3 minutes, remove the pan from the freezer. The chocolate needs to be firm enough to make curls, but not so firm that it cracks. When you press the chocolate with your finger, you should see a slight mark, but if it's too soft, you'll see a deep indentation. Put it back in the freezer for a minute if it's too soft. Use a bench scraper or metal spatula and start scraping from the bottom of the pan to form curls. Repeat until the chocolate gets too warm to make curls, then place the pan back into the freezer for a minute or so. Place the curls in a single layer and keep them cold until ready to use. You may also store these in the freezer in an airtight container with parchment between layers. Note that white chocolate is softer than semisweet and may need a higher ratio of chocolate to shortening.