This wonderfully rich Mexican dessert for bonafide Chocoholics was created by Robert Del Grande, the chef at Cafe Annie, one of the best restaurant in Houston and co-owner of the excellent Cafe Express. The custard must be refrigerated for at least 4 hours and after the dessert is cooked it must refrigerate for at least three hours. MAKE AHEAD: The pots de crème can be covered with plastic and refrigerated for up to 2 days. NOTES: The best and fastest way to melt chocolate is in the microwave oven. Chop the chocolate and then melt it in a microwave-safe bowl on high power for about 3 minutes, stirring after each minute. Alternatively, melt the chocolate in the top of a double boiler over barely simmering water, stirring frequently.