Simmer 2 cups of the milk.
Meanwhile combine remaining 1 cup of milk with the cocoa powder, sugar,
espresso, salt, chipotle, (chocolate, nibs )** and cornstarch.
Add the mix to the warm milk, bring back to a simmer, and whisk until thick,
dissolving the sugar and cocoa, about 5 minutes.
Take off the heat, add the vodka
Let cool (I fridge it for 2-3 hours until thick, or freeze for 30 minutes).
**(If you want 'crunchy' style, add the chocolate bits and nibs now instead
of above)
Process in an ice cream maker, for about 20 minutes till creamy.
Scoop out and let sit a room temperature for 10 minutes before serving.