If you want to skip the double-boiling business, throw all the ingredients but the coffee into the blender then pour in the hot coffee while the blender whizzes. Of course, melting the chocolate first lends a nicer, smoother texture. It's up to you.
Spicy Boozy Mousse
Makes about 10 small portions (2 ounces) or 4 larger portions (6 ounces)
6 ounces good-quality semi-sweet dark chocolate
3 tablespoons freshly brewed strong coffee
2 eggs*, lightly beaten
3/4 cup milk, or 1/2 cup milk and 1/4 cup cream
3 tablespoons dark rum or cognac
1 tablespoon maple syrup or sugar
1/2 teaspoon ground cinnamon
large pinch ground ancho chile pepper
Set up a double boiler by placing a metal bowl over a pot of simmering water, making sure the bottom of the bowl does not touch the water. Break chocolate into pieces and melt in the bowl, stirring occasionally. When melted, stir in coffee. Meanwhile, in a blender or food processor, combine eggs, milk, rum, maple syrup, and spices. While blender is running, pour in chocolate and coffee mixture and run until well-combined. Fill four 6-ounce ramekins or eight to ten small ceramic sake cups (usually about 2-ounces each), about 3/4 full. Chill for at least 2 hours.
*A caveat about raw eggs: if you are uncomfortable using them, you may very carefully heat them with the milk until they reach 160° F, which is basically pasteurizing them. They must be very well beaten first, and you must stir gently as you raise them to this temperature very gradually over a low flame, otherwise you will have scrambled eggs. Use a thermometer and remove from the heat as soon as they near 160°F, making sure the mixture peaks at 160°F. Then proceed with the blending process.