Ingredients
2 1/2 ounces dark chocolate, broken into pieces
1 cup water, divided
3 packets (.25 ounces each) unflavored gelatin
1 1/2 cups granulated sugar
1 cup light corn syrup
1 pinch kosher salt
1 tablespoon vanilla extract
1 cup confectioners' sugar
1 tablespoon cocoa powder
1 1/2 teaspoons ground cinnamon
Instructions
  1. Lightly grease a 9x9-inch metal baking pan with cooking spray or oil; set aside.
  2. In mini food processor, chop chocolate 45 seconds, or until the chocolate is the size of tiny pebbles; you could also use a knife or spice grinder for this. Set aside.
  3. Place 1/2 cup water in bowl of electric mixer; sprinkle gelatin over water, distributing well. Let stand while you prepare the syrup.
  4. In medium sauce pot, combine remaining water, sugar, corn syrup, and salt; cook over low heat, stirring constantly, until sugar has dissolved. Increase heat to medium; bring to a boil without stirring. Add candy thermometer; cook, without stirring, but brushing down sides with a pastry brush dipped in cold water, until the mixture registers 240° F (soft-ball stage). Let sit 1 minute.
  5. Turn electric mixer on, on low speed. Carefully pour hot sugar mixture in a stream into mixer bowl; once the mixture is incorporated, gradually increase speed to high. Beat 12-14 minutes, or until mixture is opaque and very thick. Turn mixer off. Add vanilla extract; beat 30 seconds. Add chopped chocolate and beat 15-20 seconds more, or until just melted and swirled through, but not completely combined.
  6. Immediately transfer marshmallow to the greased pan (use a greased spatula to transfer any that sticks to the bowl). Lightly wet your hands and smooth top of marshmallow. Set aside, uncovered, until firm (about 2 hours).
  7. Meanwhile, in bowl, whisk together confectioners' sugar, cocoa powder and ground cinnamon.
  8. Using scissors dipped in confectioners' sugar mixture, cut marshmallow into squares, tossing in powder and dusting off excess as you go. (They will be incredibly sticky, but as soon as you toss them in the sugar-cocoa powder mixture, they will be easy to package.) Package in an airtight box or plastic gift bag that is tied very well.