Gâteau aux Marrons
I still don't understand why there is no sweets with chestnuts in England like the US. Anyway, the rule "if I can't buy something, let's try to make it by myself" was applied here: I made chestnut cake with French chestnut puree and cooked and peeled whole chestnuts!
I adopted a recipe that I found online. The cake was wonderfully chestnut-y! I cooked soaked whole chestnuts in rum syrup for a couple of days to make the cake a bit more interesting and boozy.
Also a small amount of cocoa powder gave the cake a depth beautifully. I was very happy with the result!