Place the cognac, sherry, Cane Simple Syrup, dark chocolate syrup, half-and-half, caramel sauce and chocolate bitters if using in a cocktail shaker (without ice) and dry shake until everything is emulsified. Add large ice cubes and shake again vigorously. Double strain and serve in a martini glass or cocktail coupe. Garnish with dark cocoa powder.
Combine the sugar and 1 cup water in a small saucepan and bring to a boil. Cook, stirring, until the sugar dissolves. Remove from the heat and let cool completely. Keep covered in the refrigerator up to 1 month.