Originally posted on February 19, 2013
Okay. I know the holiday season is over and we can forget about Mel Tormé singing “Chestnuts roasting on an open fire” until next Christmas. But let’s not forget chestnuts. They are a neglected ingredient in baking: starchy and sweet, they add a unique texture to cakes and tortes. Fortunately, chestnuts imported from France are available year-round in cans, either cooked and left whole, or in purées.
Both kinds may be used in baking. Whole chestnuts, when passed through the medium or fine holes of a food mill, turn into a fluffy heap that can substitute for any ground nut in all sorts of cakes and tortes. And when used as a purée in cakes, the chestnuts add moistness and contribute a special density.
Chocolate and chestnuts are natural companions, and I couple them here in a flourless, gluten-free cake baked in a hot water bath.
For best results use a top quality bittersweet chocolate with a high cacao content.
Melt the chocolate with some dark rum in a bowl set into a pan of hot water, stirring occasionally with a whisk, until perfectly smooth.
The batter comes together very quickly in a stand mixer. Here’s what it looks like just before the beaten whites are folded in.
And here’s the batter spread in the springform pan ready to bake. Why the water bath? To insure the cake bakes uniformly all the way through. The edges will have the same texture as the cake’s center. Water temperature cannot rise above 212˚F at sea level and the cake in a water bath bakes at that temperature. A cake baked on a rack in a 350˚F oven can vary in temperature from edge to center by a few degrees, resulting in a range of textures. This is not a bad thing if that’s what you’re striving for. But the charm of this cake depends upon an even texture throughout.
And here’s the recipe.
Chocolate Chestnut Cake
9 ounces bittersweet chocolate (70-72% cacao), coarsely chopped
6 tablespoons dark rum (I use Myers’s)
1/2 cup (1 stick) unsalted butter, at room temperature
2/3 cup granulated sugar
7 large eggs, separated
1 can (15.3 ounces) unsweetened chestnut purée
1/4 teaspoon salt
1 cup heavy cream
1 teaspoon pure vanilla extract
2 tablespoons confectioners’ sugar
1. For the cake, adjust an oven rack to the lower third position and preheat the oven to 350 degrees. Butter a 9-inch spring form pan. Wrap the outside of the pan with a double thickness of heavy-duty foil; set aside. Bring a large pot of water to the boil.
2. Combine the chocolate with the rum in a small saucepan. Set the pan into a larger pan with hot water over medium heat and whisk occasionally until the chocolate is melted and the mixture is smooth. Remove the pan from the water and set it aside.
3. In a large bowl, beat the butter with an electric mixer on medium speed until it is soft and creamy, about 1 minute. Gradually beat in 1/3 cup of the sugar, and continue beating for 2 to 3 minutes until the mixture is fluffy and light. Add the yolks one at a time, beating well after each. Stop to scrape the bowl and beater occasionally. Add the chestnut puree and beat for 1 minute. Scrape the chocolate mixture into the batter (it’s all right if the chocolate is still warm) and beat it in on low speed just until incorporated.
4. In a clean bowl with clean beaters, beat the whites with the salt on medium speed until soft peaks form. While beating on medium speed, add the remaining 1/3 cup sugar 1 tablespoon at a time. Beat about 20 seconds between additions. Scrape the bowl, and beat on medium high speed until the whites form stiff, glossy peaks when the beaters are raised.
5. Stir about one-fourth of the whites into the stiff chocolate mixture. Gradually, in 3 or 4 additions, fold in the remaining whites. You needn’t do too thorough a folding job with the first 3 additions. Fold in the last of the whites only until no whites show. Scrape the batter into the prepared pan and smooth the top.
6. Set the pan into a large baking or roasting pan, and add boiling water to come halfway up the sides of the spring form. Place in the oven. Bake for 60 minutes, or until the cake feels firm on top and a toothpick comes out with just a little chocolate sticking to it.
7. Remove the cake pan with the foil from the water bath and set it onto a wire rack. When completely cool, remove the foil from around the cake pan and remove the sides of the pan. Cover the cake loosely with plastic wrap and refrigerate for an hour or two, or overnight.
8. Whip the cream, vanilla, and confectioners’ sugar until thick. To serve, dip a sharp knife into hot water, shake off the excess, and make the first cut. Continue this process of dipping and shaking with each cut. Place portions of the cake on dessert plates with a spoonful of the whipped cream alongside. Or pipe the cream through a pastry bag fitted with a star tip. Decorate each serving with a fresh raspberry. This dessert keeps well for 3 or 4 days in the refrigerator. Serve cold or at room temperature.
Makes 10 to 12 servings.