For the cupcakes: Preheat the oven to 350 degrees F. Line a standard cupcake or muffin pan with 12 cupcake liners.
In medium bowl, whisk together with an electric mixer or hand whisk the flour mix, granulated sugar, cocoa, baking powder, chipotle powder, cinnamon, salt and xanthan gum until well integrated. Add in the soy milk, oil, espresso, vanilla and vinegar, and mix until smooth.
Fill the cupcake liners three-quarters-full with batter. Place 1 chunk of chipotle chocolate into the center of each cupcake and bake until baked through, 13 to 15 minutes. Cool the cupcakes completely.
For the buttercream: Whip the powdered sugar, cocoa, butter spread, soy milk and vanilla with an electric mixer until light and fluffy. Put into a pastry bag and cut 1/2-inch off the tip.
To assemble: Generously frost the top of each cupcake with the chocolate buttercream frosting.
This recipe was created by a contestant during a cooking competition. It has not been tested for home use.