Mille-Feuille and Napoleon pastry are quite similar. Some people even consider them to be the same. Let's take a further look!
First of all, what does Mille-Feuille mean? The answer is in the simple translation of the name from French to English: A Thousand Sheets. Crispy sheets of puff pastry interleaved with cream bring a delicate contrast of crispiness and softness.
Napoleon pastry has an identical structure to Mille-Feuille, hence why many use the terms interchangeably. But are they the same? Online sources differ on the origin and definition of this delicacy. Some attribute the pastry to French and Russia, while others ascribe it to Italian chefs from the city of Naples.
Due to the lack of precise sources, we ended up observing the differences in methodology and ingredients used by online publications and aggregated the results to form a conclusion. So geeky!
Because the two pastries are very similar and the Mille-Feuille is without a doubt French, we followed the France/Russia theory presented above.
We found two often-mentioned styles of Napolean pastry: French Napoleon and Russian Napoleon.
When googling "French Napoleon pastry", most results yielded recipes that are equivalent to the classic Mille Feuille. The one little difference is that Mille-Feuille recipes use berries more often than Napoleons'.
When searching for "Russian Napoleon pastry" instead, we got more diverse results. It is taller than the Mille-Feuille and often comes in the shape of a rounded cake, instead of a square. Although the main ingredients are mostly the same, the methodology differs. The Russian 'Mille-Feuille' uses more puff sheets and more cream, which results in a taller stack and a softer core. Moreover, most Russian Napoleon recipes don't add berries between the layers, contrary to the French Mille-Feuille.
There we have it then. Mille-Feuille and French Napoleon pastry are almost the same, with the latter often using fewer berries. The Russian Napoleon pastry/cake instead has more layers, fewer to no berries, more cream and it's softer inside.