Pan-Roasted Duck Breasts with Chestnut Puree and Honey Gastrique

What I love about duck is that there are endless possibilities with every single part of this delicious bird. I’ve braised tongues and feet, stuffed duck necks, made confit of gizzard and heart, and used the rendered fat in numerous ways—poached fish in it, whisked hollandaise full of it, formed pastry dough with it; the liver (and the other f-word) seems tame after that. I’ve even had grilled duck testicles! Oddly, they didn’t sell very well at the restaurant where we prepared them; they w