Place the egg yolks in a large heat-proof bowl or the top of a conventional double boiler; set aside.
Use a conventional double boiler or a bowl that fits snugly over the top of a saucepan. Fill the bottom pan with just enough hot water that does not touch the bottom of the top pan or bowl. NOTE: The simmering water (not boiling) must never touch the bottom of the pan or bowl.
In a saucepan over medium heat, combine the sugar and water; stir until the sugar is dissolved. Increase heat to high and bring the sugar/water mixture just to a boil. As soon as the sugar/water syrup starts to boil, remove from heat, and slowly pour the mixture into the egg yolks while stirring vigorously.
Place the bowl (or top of double boiler) with the egg yolk/sugar mixture over, but not touching, the barely simmering water. Continue to whisk vigorously until the mixture is frothy and stiff, approximately 3 to 4 minutes. Remove the bowl from over the water. Using an electric mixer set on high speed, continue to beat until the mixture cools down completely, approximately 3 minutes; set aside.
In a large bowl of your electric mixer fitted with clean beaters, add the cream. Beat until soft peaks form. Using a rubber spatula, gently fold in the coffee extract, Armagnac, and the cooled egg yolk mixture.
Divide the parfait mixture evenly among 4 to 6 individual parfait glasses. Cover with plastic wrap and freeze for at least 5 hours or overnight (preferably).
Serve each parfait garnished with a dusting of cocoa or a few coffee beans, if desired.
Makes 4 to 6 servings (depending on the size of your parfait glasses).
Coffee and Armagnac Parfait - Parfait au Cafet L'Aarmagnac Recipe: https://whatscookingamerica.net/lindasandberg/desserts/coffeearmagnacparfait.htm