Triple chocolate cheesecake

First cheesecake this year. My "cheesecake monsters" (my husband and son) were already craving it so much I had to make it.  

This cheesecake is made of three chocolate layers.  Dark chocolate gives it an intense flavour that stays in contrast with subtle milk and white chocolate fillings. I used German quark (fresh and soft curd cheese). It is called topfen in Austria, serek homogenizowany in Poland, queijo fresco batido in Portugal or fromage frais in France. Quark can be easily substituted by cream cheese (because the latter is thicher you should add 3 extra tablespoons of sour cream to the filling).  

Triple chocolate cheesecake
 

23 cm (9 inches) spring cake pan


Crust:
150 g (5.5 oz) chocolate cookies
50 g (about 3 tablespoons) butter, softened



Filling:
1 kg (35 oz = 2.2 pounds ) quark cheese (20% fat content)
150 g (5.5 oz = 2/3 cup) sugar
25 g (about 3 tablespoons) cornstarch

4 eggs
150 ml (5 fl oz = 2/3 cup) sour cream
1 tablespoon vanilla extract

100 g (3.5 oz) dark chocolate
100 g (3.5 oz) milk chocolate
100 g (3.5 oz) white chocolate
4 tablespoons single cream (15% or more fat content) 


Crust:
Preheat the oven to 180ºC. Crush cookies with butter in a food processor to make fine crumbs. Press the crumbs onto the bottom of spring cake pan (previously lined with baking paper or aluminium foil, just to be sure that nothing leaks through) with the aid of the bottom of a cup. Bake for 10 - 12 min.

Filling:
Beat cheese with sugar and cornstarch until smooth. With the mixer still running add eggs one at a time, then sour cream and vanilla extract. Mix briefly, only to combine the ingredients. 


Preheat the oven to 180ºC. In 3 medium bowls melt 3 types of chocolate with single cream added, starting with white, then milk and finally dark (to white and milk chocolate add 1 tablespoon of cream, to the dark one 2 tablespoons). This can be done in "bain marie" or in a microwave (I melt my chocolate at 360 W in 50 seconds, take it out and mix it energetically to melt completely). 


Leave melted chocolate to cool a little. To each bowl with chocolate add gradually about 1/3 of cheese filling(it was about 500 g of added filling to each bowl ) and whisk througoutly until smooth. Initially it may seem that you finish with lumps of chocolate in filling, but they all disappear as you whisk. 


Pour the white chocolate filling onto the cooled crust. Then, very carefully and evenly, spoon the milk chocolate filling and spread it gently to create a second layer. Next goes the dark chocolate filling and you get a third layer. 


Bake in the oven for 15 minutes at 180ºC, lower the temperature to 160°C and continue to bake for 1 hour - 1 hour 15 minutes , until it is set on the sides and a little shiny and moist in the center. Turn the oven off and leave the cake to cool inside with the door slightly open.