2 vanilla beans
4 cups granulated sugar
1½ lbs. good quality semi-sweet chocolate, coarsely chopped
9 oz. good quality bittersweet chocolate, coarsely chopped
2 cups Dutch-process cocoa powder
Split and scrape the vanilla beans and combine in a large bowl or jar with the sugar. Work the vanilla seeds into the sugar with your fingers. Bury the pods under the sugar, cover tightly and let stand overnight (or up to months) at room temperature. Remove the pods when ready to use.
In the bowl of a food processor fitted with the metal blade, combine the sugar, semisweet and bittersweet chocolate, and Dutch process cocoa powder. Process in 4-second pulses until the chocolate is very finely ground and the mixture is well combined. Store the mix in an airtight container for up to 6 months.
Combine 2 tablespoons cocoa mix with 8 oz. of very warm milk and stir to combine until well blended.