I was in search of a cocktail that made good use of the Fee Bros. Aztec chocolate bitters I had picked up, and then I remembered a chipotle martini experiment I had invented, and it seemed the two would go well together. 

And they do!  The bitters give this drink a lovely gold tone, and the chocolate and spice are a wonderful combination.

• 1-1/2 oz Hangar One chipotle vodka*
• 3 oz Beefeater gin (I'm sure you could substitute another gin, but make sure it's not anything too delicate)
  
• 1/2 oz dry vermouth (more or less to taste
• 2 or 3 dashes Fees Bros Aztec chocolate bitters

Stir with ice until cold.  Strain into a cocktail glass.

* This is a small batch, limited edition "Alchemist Series" vodka from Hangar One.  As far as I know, it actually has been two of their three batches of Alchemist Series vodkas (the other being a wasabi vodka). I suppose it's possible they will make it part of their regular production. We found our bottles (we've bought three so far) at K&L Wine Merchants.