This sounds like the famous Karpatka, or “Carpathian Mountain Cake.” It is a legendary Polish dessert named after the Carpathian Mountains because the irregular, craggy top of the pastry looks like a snow-capped mountain range.

It consists of two layers of choux pastry (the same dough used for cream puffs) sandwiched around a thick, luxurious vanilla milk pudding. It’s addictive because it’s airy, creamy, and not overly sweet.

🏔️ Polish “Karpatka” Pudding Cake

1. The “Mountain” Pastry

• 1 cup Water
• ½ cup (125g) Butter
• 1 cup All-purpose flour
• 5 Large eggs
• ½ tsp Baking powder

The Method:

1. Boil water and butter in a pot. Add flour all at once and stir vigorously until a dough ball forms. Let it cool for 10 minutes.
2. Beat in the eggs one by one until smooth. Stir in the baking powder.
3. Spread half the dough on a parchment-lined baking sheet (about 9×13 inch). Do not smooth it out! Leave it bumpy.
4. Bake at 200°C (400°F) for 20–25 minutes until golden. Repeat with the second half of the dough.

2. The “Addictive” Vanilla Pudding

• 3 cups (750ml) Milk
• ¾ cup Sugar
• 2 tbsp Cornstarch + 2 tbsp All-purpose flour
• 2 Egg yolks
• 1 tsp Vanilla extract
• 1 cup (225g) Butter (room temperature)

The Method:

1. Whisk 1 cup of milk with the flour, starch, and yolks.
2. Boil the remaining milk with sugar and vanilla. Pour the starch mixture in and whisk constantly until it becomes a very thick custard. Let it cool completely.
3. Cream the room-temperature butter until fluffy, then add the cooled custard spoon by spoon until you have a rich, silky cream.

3. The Assembly

1. Place one sheet of baked pastry in your dish.
2. Spread all the pudding cream over it.
3. Top with the second “mountainous” pastry sheet.
4. Important: Chill for at least 3 hours so the pudding sets.

💡 Why This Cake is Iconic

• The Texture: The pastry is crispy and hollow, while the pudding is dense and buttery.
• The Appearance: Just before serving, dust it heavily with powdered sugar. The sugar settles in the “valleys” of the dough, making it look like a mountain range covered in snow.

👵 The “Lazy” Polish Shortcut

If making choux pastry feels like too much work, Polish grandmothers often make a version using store-bought puff pastry. It won’t have the “mountain” peaks, but the taste of the vanilla pudding between the flaky layers is just as heavenly.

🍽️ Serving Tip

Cut it with a serrated knife to avoid squishing the cream out of the sides!