1 tablespoon coffee-flavored liqueur (such as Kahlua®)
1 1/2 teaspoons instant coffee granules
1 teaspoon unsweetened cocoa powder
1/4 cup ice cold heavy whipping cream
1 tablespoon white sugar
1 teaspoon whipped cream for garnish (optional)
1 pinch unsweetened cocoa powder for dusting (optional)
8 h 18 m
Whisk eggs, sugar, coffee-flavored liqueur, instant coffee, and 1 teaspoon cocoa powder together in a metal bowl.
Place bowl over low heat on the stove (holding bowl with a dishtowel) and continue whisking until mixture thickens, 4 to 6 minutes. Whisk continually to prevent eggs from scrambling. Remove bowl from heat and let mixture cool completely. (You can set the bowl on ice water to speed this up.)
Whisk ice-cold heavy cream and sugar together in a chilled bowl until stiff peaks form, 3 to 4 minutes. Add cooled egg-coffee mixture to the whipped cream. Stir with a spatula until just combined.
Transfer mixture to serving cups. Wrap cups in plastic wrap and freeze until firm, 8 hours or overnight. Garnish with whipped cream and a dusting of cocoa powder.
Answering questions about how to use this technique to make other flavors is tough, since there are many variables. Theoretically, if you replace the coffee and liquor, with other similar “stuff,” then you should get a similar product. Good luck!