Texas Sheet Cake Cookies - Crystal Sugar

Ingredients

• 1/2 cup unsalted butter, softened
• 1/2 cup Crystal Sugar Extra Fine Granulated Sugar
• 1 whole large egg
• 1 teaspoon vanilla extract
• 3 tablespoons cocoa powder
• 1 teaspoon baking powder
• 1/2 teaspoon salt
• 1/2 teaspoon cinnamon, optional
• 1 1/3 cups all-purpose flour*
• 1/2 cup semi-sweet chocolate, melted
• 1/2 cup unsalted butter
• 2 tablespoons cocoa powder
• 3 tablespoons milk
• 1 teaspoon white vinegar
• 2 1/2 cups Crystal Sugar Confectioners Powdered Sugar