Ingredients:

• For the filling:
  2 eggs
  400 g Greek yogurt or sour cream
  150 g sugar
  1 teaspoon vanilla sugar
  50 g flour or corn starch
  100 g butter at room temperature
• For the base:
  300g chocolate biscuits
  1 tsp vanilla sugar
• In a saucepan, mix eggs and yogurt.
• Then add the sugar, vanilla sugar and flour.
• Mix well, then put on the heat and bake over medium-low heat until it thickens.
• Cover with cling film and leave to cool to room temperature.
• Now prepare the base by finely blending the biscuits.
• Mix them with the vanilla sugar, melted butter and milk.
• Line the bottom and sides of a cake tin with this mixture and flatten.
• Separately, whip the butter for 4-5 minutes, then gradually add the cream you prepared earlier.
• Pour the mixture onto the biscuit base.
• Cover with more crushed biscuits.
• Decorate with some hazelnuts on top.
• Leave to cool overnight in the refrigerator before serving.
• 
  120g melted butter
  1 tbsp milk