Originally from "Who can make iron chef Sakai's cakes? " On the matter of the so-called "Japanese Christmas cake" and the Mont Blanc (chestnut puree cake):

Ladycake (Ladycake) said:
>I do not mean for this to sound disrespectful >at all, but does this sound Japanese to anybody >else? These cakes all sound European to me. >Anybody else have a comment here?

On Christmas cakes: What I meant to stress was that in the US, a "Christmas cake" means a molded fruit-cake with red and green colored maracino cherries inside, the kind that Auntie so-and-so sends us every holiday season; but if you say "Christmas cake" to a Japanese person, he'll think it's a whipped cream/strawberry cake.

On the Mont Blanc: The cake is named after a mountain in the Alps, so yes it is certainly a European recipe. all I meant to say was that it can be found in every corner pastry shop in Japan, but can be found in no corner pastry shop in the US.

I'll give an overview of traditional Japanese dessert or "wa-gashi" and fetch pics searched using googles to illustrate.

Chestnut
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Chestnut "kuri" is used a lot in Japan in both traditional and western desserts in Japan.

In Japan the chestnut is very often dyed yellow using the "kuchinashi" or the seed-pod of the gardenia flower.
These yellowed sweetened chestnut can be bought in small jars.
(pic: http://www.city.sasayama.hyogo.jp/mikaku/rckrkanroni.html)

There is also something called the "kuri-kinton". Traditional New Year's dessert "kinton" is typically a sweetened sweet potato paste with pieces of chestnut. (middle of - http://www.kibun.co.jp/enter/shogatu2001/syouhin/products-shogatu03.html)
This word "kuri-kinton" can also mean something made entirely from strained/pureed chestnut as in (bottom of - www.pref.gifu.jp/ kodomo/shoku/).
"kinton" can also be applied to a type of high-end traditional Japanese desert. (go to www.gld.mmtr.or.jp/~shokado/ winter.htm and all the frazzled or shaggy-looking ones are of this "kinton" variety).

Chestnuts are also put inside the "yokan" -- which is a molded bar of smoothly strained adzuki bean paste.
A softer variety of this is called the "kuri-mushi-yokan".
(at www.nande.com/kameki/, the brown bar with chunks of chestnut.)

I should also say that this bright yellow coloring is always used in the Mont Blanc pastries sold in Japan -- so the chestnut creme is a bright yellow color as well. So you can say this is a traditional Japanese adaptation to a European recipe.

Mochi, Adzuki
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I'd say the most basic Japanese dessert are the ones in the "mochi-gashi" category. The "mochi" being a dough made from pounding steamed "sticky rice" (or "sweet rice").
Examples of this are the "daifuku" (www.futabado.com/siomame.htm), which is the most basic type, and the green "kusa-mochi" (2nd row, 3rd from left www6.ocn.ne.jp/~aoki3386/) which is flavored with mugwort/wormwood, but I think nowadays fresh herb is rarely used and you can certainly taste the difference.

The filling inside these is called "an", however if you say "an", it is usually taken to mean an adzuki-bean paste.
Adzuki-bean paste is to the traditional Japanese dessert what chocolate is to western dessert.

I can list some more novelty ingredients, etc. if anyone's interested.