Mexican chocolate is not your average chocolate. Made from ground roasted cocao nibs, sugar, and cinnamon, it has a slightly granular texture and a distinctive spiced flavor. Besides cinnamon, Mexican chocolate may also contain other spices like nutmeg or allspice, as well as chilies for heat, and nuts for texture. Though Mexican chocolate is often used make hot chocolate, it is also a key ingredient in traditional dishes like mole.
For 4 oz. of Mexican chocolate, substitute 4 oz. semisweet chocolate plus 2 Tbs. granulated sugar and 1/4 tsp. ground cinnamon.
Mexican chocolate is sold in solid bars and discs, as well as in powdered and syrup form. It's available in many well-stocked grocery stores, and in Latin markets.