The King of Napoleons

I’m sharing my version of The King of Napoleons, a decadent Russian-style Napoleon cake made with ultra-thin puff pastry layers and a rich, creamy custard buttercream—often topped with fresh berries and a dusting of powdered sugar.

Why I’ll Love This Recipe

I love how the combination of crisp flaky pastry and creamy custard delivers amazing texture. I can decide whether I want it crunchy just after assembly or perfectly soft after a day or two in the fridge. The rectangular version simplifies cutting and serving for a crowd, and adding berries gives it a fresh burst of flavor.

ingredients

(Here’s a tip: Check out the full list of ingredients and measurements in the recipe card below.)
Quick Puff Pastry:

• unsalted butter, cold or frozen, cubed

• eggs

• cold water

• sifted all‑purpose flour

• white vinegar

• salt

Egg Yolk Custard:

• egg yolks

• granulated sugar

• whole milk

• vanilla extract

• sifted all‑purpose flour

• unsalted butter

Optional topping: berries (such as raspberries, blueberries, blackberries) and powdered sugar

directions

1. Make the puff pastry – whisk eggs, salt, water, vinegar. pulse cold butter and flour until pea‑size; combine with egg mixture to form dough; divide into 4 disks and refrigerate 1–2 hours.

2. Bake layers – preheat oven to 400 °F. Roll each dough disk into a thin rectangle or circle (~12½-inch). Prick with fork and bake 5–7 minutes until lightly golden. Trim to shape and save scraps.

3. Make custard – whisk egg yolks, sugar, and flour into lump-free batter using a bit of milk to ease mixing. Heat the rest of the milk to boiling, temper yolk mix, then bring to boil again, stirring constantly. Add vanilla and butter; strain if necessary; cool to room temperature.

4. Assemble – place one pastry layer and brush a dab of custard beneath to anchor. Layer custard between all sheets. Cover top and sides with remaining custard. Press cake scraps onto sides and sprinkle on top.

5. Decorate – top with fresh berries and mint leaves, dust with powdered sugar for finish.

Servings and timing

This recipe yields about 24 servings for an 11″ round cake or the equivalent in rectangular form. Prep & bake time is around 2 hours 30 minutes (about 1 h 30 m prep + 1 h cooking).
If assembled 3 hours before serving, pastry stays crisp; for soft, tender cake allow 24–48 hours for the layers to absorb custard fully.

Variations

• Use store‑bought puff pastry to save time—just roll very thin and bake.

• Try different fruit toppings (strawberries, sliced apricot) or add edible flowers for aesthetics.

• Make the round version or rectangular by rolling four pastry slabs to fit pans or sheet trays.

storage/reheating

I refrigerate this cake covered for up to 2–3 days. For a soft cake, let it sit in fridge for at least 24 hours. If crisp is preferred, refrigerate only briefly before serving. I don’t reheat it—best served chilled or at room temperature.

FAQs

What’s the difference between French and Russian Napoleon cake?

I make the Russian style here—many ultra-thin puff pastry layers sandwiched with custard which soften over time. French mille‑feuille uses fewer layers and stays crisp.

Can I make it ahead?

Yes—I can assemble it up to 48 hours before serving. It becomes soft and tender if left covered in fridge. Or I can assemble just a few hours before if I want it crispy.

What if my custard has lumps?

If your custard is grainy or clumpy, I run it through a fine mesh sieve or pulse with an immersion blender while still warm for smooth texture.

How do I use the pastry scraps?

I crumble saved scraps and press them onto the cake’s sides and sprinkle on the top. They also help prevent a skin forming on the custard and add extra decoration.

Conclusion

I love this version of The King of Napoleons because it’s both elegant and flexible. Whether I want crisp flaky layers right away or an indulgently soft custard-soaked cake later, it delivers. Rolling it rectangular makes portioning simple and crowd‑friendly. I hope when I try making this I enjoy every creamy, flaky bite as much as I do!

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