Finely chop the chocolate. Dissolve the coffee in 1 tablespoon of hot water. Separate the eggs into egg yolks and whites.

Put the chocolate and butter in a bowl, and melt in a double boiler at 45 ~ 50℃ (110 ~ 120°F).

Remove the mixture from the double boiler. Add coffee and stir.

Add the egg yolks one by one, and mix.

Pour the egg whites in a different bowl. Whip until it forms stiff peaks to make a meringue.

Add 1/3 of the meringue to Step 4 and mix it 5 ~ 6 times in a circular motion.

Add the remaining meringue, and fold it in with a diagonal cutting motion. Don't mix too much.

Pour into molds, and chill well in the fridge. (At least for 4 hours.)

Whip the heavy cream until it has thickened.

Pour it on top of the chilled mousse and serve!