Chocolate Sauce

Source:  Lenotre's Desserts and Pastries

9 ounces semi-sweet chocolate (I used 9 ounces of Callebaut Milk Chocolate)
1 cup milk
5 teaspoons creme fraiche or heavy cream
1/4 cup granulated sugar
2 1/2 tablespoons butter

Melt chocolate in double boiler.  Bring milk to a boil, add the creme fraiche and bring back to a boil.  Remove the pot from the heat, stir in the sugar, the melted chocolate and the butter.  Replace the pot on the stove and boil the sauce for a few seconds.  Pour into a bowl and cool.