If it's the big cake it kinda looks like a "fraisier" which is basically a strawberry cake, or in French a "gâteau aux fraises"
(gâteau = cake, fraises = strawberries)
Château
( = castle) and gâteau sound almost the same, so we probably have a perfect example of what we call Franponais: French words used by Japaneses to sound cool, if you know some French look it up it can be really fun!
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