Note: Adapted from "La Bonne Cuisine de Madame E. Saint-Ange." Three-quart charlotte molds are available from Ambassador Fine Foods in Van Nuys, (818) 787-2000; www.culinary-direct.com; and www.bridgekitchenware.com. Or you may use a 7-inch springform pan.
1 vanilla bean
6 tablespoons sugar
Cut the vanilla bean into extremely small pieces with scissors. Put the vanilla bean pieces and 3 tablespoons sugar in a mortar. Crush together with a pestle. Strain through a fine sieve, add another 3 tablespoons sugar and repeat the process.
50 chestnuts (about 2 pounds)
1 1/3 cups superfine sugar
5 eggs, separated
A good pinch of powdered vanilla
3/4 cup plus 2 tablespoons (1 3/4 sticks) butter, softened, plus more for the pan
1. Make a cut around the perimeter of each chestnut shell and plunge them into boiling water for 1 minute, then peel them.
2. Bring 2 cups of water to a boil and add the chestnuts. Reduce the heat to a simmer, cover and cook gently until the pulp is transparent when you cut into a chestnut, 25 to 30 minutes. Overcooking will allow the chestnuts to absorb too much liquid.
3. While the chestnuts are still burning hot, force them through a tamis or fine sieve, four to five at a time, collecting the puree in a bowl.
4. Mix the puree with a wooden spoon and stir in the sugar. It will melt and dilute the puree. Then add the egg yolks, one at a time, beating the puree vigorously as you go. Stir in the vanilla powder.
5. Beat the butter until it is soft and creamy and beat that into the batter.
6. Butter a charlotte mold. Heat oven to 350 degrees.
7. Whisk the egg whites to firm peaks. Using a spatula, thoroughly mix one-fourth of them into the batter. Spread the remaining whites on top of the batter and then fold them together: Cut into the whole mixture with the spatula, so that you pass under the mass, turning it and placing it over the whites. Turn the bowl and repeat until the batter and whites are thoroughly mixed together. You must do this with large, generous gestures, measured yet swift, going out from the middle to the edges, continually turning the bowl on the table.