While plenty of places offer single-origin chocolate, this confectionery in the Juárez neighborhood of Mexico City takes the concept to the next level. At La Rifa Chocolatería, every aspect of the supply chain is traceable and transparent. Ask where the honey, unrefined piloncillo sugar, or, of course, cacao nibs come from and the staff here can rattle off not only its microregion and village of origin, but also the names of the producers who made it. Since starting the business in 2012, co-founders Daniel Reza and Monica Ortiz Lozano have…