A can of chestnuts left from a photo shoot sat in the cabinet for a couple of months until I found this recipe in one of my favorite books, The Art of Quick Breads by Beth Hensperger. It's just amazingly delicious.
Preheat oven to 325 degrees. Grease a bundt pan, 10-inch tube pan or two 9-inch loaf pans.
Combine the flour, baking powder, baking soda and salt in a medium bowl.
Beat the butter and sugar until fluffy. Add the eggs and beat well. Beat in vanilla and sour cream.
Add the flour mixture to the sour cream mixture and mix well. The mixture will be very thick, possibly too thick for an electric mixer.
Remove 1 cup of the mixture to another bowl. Add the chestnut puree and chocolate chips and mix well.
Spoon half of the batter into the bundt pan and top with half the chestnut batter. Another layer of vanilla batter, then the remaining chestnut batter. Insert a butter knife through the batter layers and swirl once or twice to marble the batter.
Bake 60 to 65 minutes for tube pans and 45 to 50 minutes for loaf pans, until the top of the cake is no longer shiny and a tester comes out clean.
Cool slightly, remove from pan, and dust with a mixture of powdered sugar and cocoa powder. Cake freezes for up to 2 months.