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.
Pour the cream and vanilla and whisk to blend.
Pour the chocolate mixture into the cream mixture and blend.
Cover and refrigerate until cold for 1 to 2 hours
Transfer the mixture to an ice cream maker and freeze by following the manufacturer`s instructions.