Melt the unsweetened chocolate on top of a double boiler over hot boiling water.
Gradually whisk the cocoa in the heat and stir constantly until smooth.
:-The chocolate may "seize" or clump together. Don`t worry, the milk will dissolve it.
Whisk in the milk, a little at a time, and heat until completely blended.
Remove from the heat and let cool.
Whisk the eggs in a mixing bowl until light and fluffy for 1 to 2 minutes.
Whisk in the sugar, a little at a time, then continue whisking until completely blended. Mix it in the chocolate mixture.