I really like this pistachio paste, but haven't seen it anywhere except on Amazon. Unfortunately it is currently out of stock, which is very sad for me, since my jar has only a few teaspoons left. I can't attest to cooking with it, since mostly I either put it on toast or just spoon it from the jar and get transported. Very very good. And not cheap, of course.
https://www.amazon.com/gp/product/B0763T4QWS/ref=ox_sc_saved_image_6?smid=&psc=1
Pistachio isn't really on topic, though. As for chestnuts I've always loved them roasted from a cart on the street, but strangely I don't like chestnut desserts.