Blood Orange Cake All Over the Place

Besides the soda bread (see previous post), this month's Bon Appetit also has a recipe for and gorgeous photo of a blood orange upside down cake with polenta. My friend Nancy made it for our book club meeting this week, and served it with creme fraiche, and it was a sensation. I decided I had to bake it, too, and I did on Friday (that's mine in the photo above). We all enjoyed it, although the boys were not quite as enthusiastic as the book club had been. Then tonight, we went out to dinner at Flour + Water (hot restaurant in the Mission featured in the NY Times a few months ago with outstanding pizzas and pastas). And what was on their dessert menu? The blood orange upside-down cake with polenta. Of course we had to try it. It was the same exact cake, except made into an individual cake with one slice of carmelized blood orange on top. The cake was just a tad lighter (maybe more egg whites? cake flour?) but still with the crunch of polenta. And I believe they went for whipped cream on the side. What I want to know is, did Flour + Water see Bon Appetit and decide they had to make this cake, too? Or did some pastry chef create it elsewhere and Bon Appetit jumped in with its own version? Or is it just one of those recipes floating out there whose time is now? (Bon Appetit is growing on me, but I still miss Gourmet.) As good as it is, I think I have had enough blood orange upside down cake for a while now.