Roughly chop the chocolate and place in a mixing bowl. Carefully heat the cream in a saucepan. Just before it starts to boil, remove the pan from the heat and pour over the chocolate into the bowl. Wait two minutes, then stir together the cream and chocolate with a spoon until you get a homogeneous mixture. Now add the butter and stir in as well. Set the chocolate mass / canache aside to cool.
Spread a teaspoon of apricot jam on each of the eight cake layers. Sprinkle the tartlets with brittle as desired, carefully pour the cooled canache over it and decorate with brittle as desired.
Chill the tartlets in the refrigerator for 1 - 2 hours or until they are ready to be eaten.