Preheat the oven to 350 degrees and butter a 5 cup souffle or baking dish. In a food processor pulse 4 cups of the corn kernels (reserving 1 cup) for 5 to 10 seconds, scraping down the bowl to get the mixture to move freely. Continue processing until the corn is pureed. In a medium saucepan, melt the butter over medium heat. Add the pureed corn and 1 teaspoon of the sugar. Cook for 2 to 3 minutes, stirring occasionally, until the mixture has thickened to coating consistency.
Transfer the pureed corn to a large mixing bowl and set aside to cool. Fill a large deep
saucepan about 1/3 full with chicken stock and add the celery, carrot, peppercorns, and salt
(there should be just enough stock to cover the chicken breasts). Bring the stock to a boil
over high heat. Season the chicken well, add it to the pan and reduce the heat. Partially cover the pan and simmer for about 12 minutes, then remove from the heat, add the pitted prunes to the pan to soak, and let the chicken cool until it is just warmer than room temperature. Remove the chicken and the prunes. Cut the chicken meat into 1inch cubes, discarding the skin and bone. Coarsely chop the prunes and set them both aside. In a large deep skillet, heat the olive oil over medium low heat. Add the onions and saute for one minute, stirring. Sprinkle with the remaining 1 teaspoon sugar, cover the pan and let the onions cook for 4 or 5 minutes, until softened. Uncover the pan and increase the heat to medium. Continue cooking until the excess liquid has evaporated, without browning the onions. Drain the chopped tomatoes, then add them to the pan. Continue cooking until the excess moisture has evaporated, about 10 minutes. Add the chicken, prunes, and the reserved cup of corn kernels to the pan and remove it from the heat. In the bowl of an electric mixer or with a hand mixer, beat the egg yolks until they are pale and thickened. Add the pureed corn mixture and mix to combine. Spread half of the yolk corn mixture over the base of the pan, then carefully spoon the chicken mixture over the corn in an even layer. Cover with the remaining yolk corn mixture in an even layer and brush the top lightly with the beaten egg yolk. Bake in the center of the oven for 35 to 40 minutes, or until the top is golden brown. Let rest for 5 minutes, then serve.
c.1997, M.S. Milliken & S. Feniger, all rights reserved