Gâteau “Karpatka” Polonais

When the milk is hot (but not boiling), remove the vanilla pod. Slowly pour the milk over the egg mixture while whisking.
Pour everything back into the saucepan, then heat over medium heat while stirring constantly until the cream thickens and becomes creamy.
Incorporate the butter:

Remove the cream from the heat and stir in the butter cut into small pieces. Mix until completely melted and the cream is smooth. Let cool to room temperature.
Step 3: Assembling the cake

Assemble the Karpatka:

Take one of the cooled choux pastry rectangles and place it on a serving dish.
Spread the pastry cream evenly over this first rectangle.
Add the second rectangle:

Carefully place the second rectangle of choux pastry on the cream, taking care not to crush it.
Decoration (optional):

Dust the cake with icing sugar, or use melted chocolate or cocoa powder for a gourmet touch.
Refrigeration:

Let the Karpatka sit in the refrigerator for at least 2 hours before cutting. This allows the cream to firm up and the flavors to blend.
Step 4: Serving
Cut and serve:
Use a sharp knife to cut the cake into portions. Serve chilled with coffee or tea.
Additional tips
For a flavor variation, you can add a teaspoon of instant coffee to the custard or replace some of the milk with cream for an even richer texture.
You can also incorporate fruit or toasted nuts into the custard for a crunchy touch.
Enjoy!