The duck fat doughnut is a savory miracle. We love this recipe by the incomparable Ian Knauer from  Gourmet magazine, and we continue to believe it is the best doughnut ever. But we might be biased. There is a lot of duck involved. It’s a perfect recipe for Hanukkah, or for that rarest of holidays, Thanksgivukkah. Sufganiyot, or doughnuts,…