Napoleon cake

Ingredients:

Cakes

• 4 tbsp (60 g) butter, softened
• 1 tbsp. sugar
• The whites of 2 large eggs (room temperature, well beaten)
• 1 cup sour cream (room temperature)
• 1 tbsp. vodka
• 1 pinch of salt
• 2 cups premium flour

Custard

• 6 cups whole milk
• 10 large egg yolks (room temperature)
• White of 1 large egg (room temperature)
• 2.5 cups of sugar
• 6 tablespoons flour
• 1 tbsp vanilla extract
• 16 tbsp (230 g) butter

Preparation:

1. Knead the puff pastry.
   
   In a large bowl, beat 60 g of butter and 1 tbsp of sugar until creamy. Stir in 2 stiffly beaten egg whites, sour cream, vodka, and salt. Gently fold in the flour, one spoon at a time, until the dough is soft and pliable. You may not need all the flour.
2. Wrap the dough in cling film and refrigerate for 1–2 hours to make it easier to work with.
3. Bake the dough layers.
   
   Preheat oven to 190°C (375°F). Grease a baking sheet with butter and lightly dust with flour. Divide the dough into 16 pieces. Roll each portion directly on the prepared baking sheet into a very thin circle 20 cm in diameter. (If your baking sheet can fit two circles, that's great.)
   
   Bake the cakes until golden brown, about 6 to 10 minutes. If the dough puffs up, pierce it with a fork.
   
   Place each finished cake layer on a wire rack to cool. Bake all the dough portions in this manner.
4. Prepare the custard.
   
   Pour the milk into a large saucepan and heat, but do not boil.
   
   In a large bowl, beat the yolks, 1 egg white, and 2.5 cups of sugar until creamy. Add 6 tablespoons of flour and mix well.
   
   Pour this mixture into the warm (but not scalding) milk in a saucepan, stirring constantly, first with a whisk until smooth, then with a wooden spoon until the cream thickens over low heat. Add vanilla and 230 g of butter. Stir the cream until smooth.
5. Remove the pan from the stove and let it cool, stirring the cream frequently.
6. Assemble the cake.
   
   Place one cake layer in a 20 cm springform pan and evenly cover it with a layer of cooled custard. Continue assembling the cake in this manner, finishing with the 15th cake layer with the custard.
7. Crumble the last 16th layer of cake and sprinkle it over the cake. Refrigerate for 5-6 hours.
   
   Before serving, run a knife between the cake and the sides of the pan. Remove the pan and, using a cake spatula or two regular spatulas, carefully transfer the cake to a serving platter. Use an electric knife to cut it into neat, even slices and serve.