Quark Streusel Apple Cake

Ingredients for the Crust + Streusel:

• 1 cup soft butter (250g)
• 3/4 cup sugar (150g)
• 1 packet vanilla sugar
• 1 egg
• 1 packet baking powder
• 3 1/2 cups all-purpose flour (450g) + 2 tablespoons for the streusel

For the Cream:

• 2 1/2 cups sour cream (600g)
• 2 cups quark (40% fat)
• 1 cup heavy cream
• 1 cup sugar (200g)
• 1 packet vanilla sugar
• 4 eggs
• 2 packets vanilla pudding powder

For the Apple Filling:

• 4-5 apples
• 2 tablespoons sugar
• 1/2 teaspoon cinnamon

Baking Time: Bake in a preheated oven at 160°C (320°F) in conventional mode for about 45 minutes.