Over low heat, melt xylitol. This takes approximately 5 minutes, depending on the exact heat setting, being careful not to burn. If you have a candy thermometer, it should read above 300F (mine was at 350F).
While xylitol is melting, line a jelly roll pan with parchment paper. Remove xylitol from heat and let cool about 10 minutes or until the thermometer reads 275F or less. Add peppermint extract and stir to mix. (Adding peppermint extract to the xylitol at higher temps could cause it to spatter) Pour out into the center of parchment and spread out as best you can. Please use caution, as this liquid is extremely hot.
Let dry. This will take up to 24 hours. As it dries, it forms these cool looking star shapes.
I let mine dry overnight, then turned it in the morning. The bottom was still wet in the center. As it dries, break apart to help further drying. When dry it will be opaque white and be covered with the star design. When completely dry, break into serving sized (1 gram) pieces.