Chestnut bread is one I like in the fall and winter. Especially lovely is the sweet nut flavor paired with a bit of saucisson or cheese. Recently I revisited my formula for 60/40 wheat and chestnut and decided to use rye sour to ferment the loaf, as I wasn't happy with one I'd made with wheat. This time the loaf was sensational. The crumb while not quite holey still showed signs of aveolage. The rye imbued a sweeter and more complex flavor, and the color was almost a purple grey hue almost a chocolate flavor, kind of like roasted chestnuts in fact!