Mix the cottage cheese with a hand blender or mixer until the cheese is silky smooth and no grains are visible. Mix the cottage cheese, cream cheese, eggs, sugar, salt and vanilla pulp thoroughly. If the mixture is too liquid, add 1 tablespoon of cornflour. Remove about 1/8 litre of the mixture and pour into a bowl. Grind 30 g pistachios finely and stir into the mixture.
Oil a springform pan (18 cm Ø) thinly and line the bottom of the pan with baking paper. Pour in the white cheese cream. Spoon the green cheese cream onto it by the spoonful and fold it in lightly with a fork, so that a nice marbling is created. Place the springform pan on a large sheet of aluminium foil and press the foil firmly against the edge all the way round to make the pan watertight. Place the springform pan in a large casserole dish and pour on hot water about 2 cm high. Bake the cake in a preheated oven (electric range: 175 °C/ convection oven: not suitable/ gas: level 2) on the bottom shelf for about 1 1/2 hours. Let the cake rest in the pan overnight and let it cool down. Carefully remove the cake from the tin. Wash the blueberries, drain and spread on the cake.
Bake the cake in a preheated oven (electric range: 175 °C/ convection oven: not suitable/ gas: level 2) on the bottom shelf for about 1 1/2 hours. Let the cake rest in the pan overnight and let it cool down. Carefully remove the cake from the tin. Wash the blueberries, drain and spread on the cake. Finely chop the remaining pistachios. Dust the cake with icing sugar and sprinkle the edge with pistachios