In a large bowl, place the chopped chocolate and set aside.
Pour the milk, cream, and vanilla into a medium saucepan, and place over medium heat. Cook to a simmer.
As the milk is warming, mix the egg yolks and sugar until completely blended.
Once the milk reaches a simmer, remove it from the heat and slowly drizzle it into the egg yolk mixture, a tablespoon at a time while constantly stirring.
Run the mixture through a sieve then return to the saucepan and place back over the stove.
Cook over medium heat while you constantly stirring, until the mixture has thickened. The way to know is by dipping a wooden spoon into the mixture and then running your finger through the middle, if there is a noticeable line then it is ready.
Remove from the stove, and pour it over the chopped chocolate. Allow it to sit for a few minutes.
Gently stir the chocolate until you have a smooth and shiny cream.
Place a plastic wrap over the surface of the chocolate and allow it to set. Or use it as instructed in your recipe.