One of my favorite roasters, Onyx Coffee, now makes coffee extractions to be used in cocktails, cold drinks, etc. Much easier than making espressos, and very useful for people who don't have an espresso maker. Here's today's cocktail, using their recipe. Note that I split this drink in two so that N and I wouldn't need a nap afterwards.
Espresso MartinI, Onyx Style
1 1/2 oz. Onyx Coffee Extractions
2 oz. vodka
1/2 oz. coffee liqueur (I used Kahlua--all I had)
1/2 oz. simple syrup (I used Demerara syrup)
Shake over ice and strain into a martini or coupe glass.