- 36 pitted prunes (about 13 ounces)
- 1 vanilla bean, split lengthwise
- 1/2 teaspoon crushed fennel seeds, tied in a piece of cheesecloth
- 1 1/2 cups fruity red wine
- 1 1/2 cups Armagnac
- 1/3 cup sugar, plus more for dusting
- 3/4 cup milk
- 2 tablespoons all-purpose flour
- 8 large egg yolks
- 10 large egg whites
- Pinch of salt
- Sweetened whipped cream, for serving
- In a heatproof bowl, combine the prunes, vanilla bean and fennel seed bag. In a medium saucepan, bring the wine and Armagnac to a boil. Pour over the prunes; let cool. Cover with plastic and let the prunes macerate for 2 days.
- Preheat the oven to 375°. Butter a 10-inch springform pan and lightly dust it with sugar. In a medium saucepan, bring the prunes and their soaking liquid to a boil. Reduce the heat to low and simmer until a syrup forms, about 25 minutes. Strain the prunes over a bowl; remove the fennel seed bag and squeeze the syrup back into the pan. Remove the vanilla bean; scrape the seeds into the syrup and stir. Reserve 12 plump prunes in the syrup. Finely chop the remaining prunes.
- In a small saucepan, bring the milk to a simmer. Pour it into a large bowl. Whisk in the flour and 8 egg yolks, 1 at a time. Stir in the chopped prunes.
- In a large bowl, beat the egg whites until soft peaks form. Gradually beat in the 1/3 cup of sugar with the salt; beat until the whites are stiff and glossy. Fold one-third of the beaten whites into the prune-egg mixture, then fold in the rest.
- Scrape the batter into the pan and bake in the center of the oven for 40 minutes, or until risen and golden brown. Let cool on a rack for at least 30 minutes.
- Preheat the oven to 400°. Run a knife around the soufflé and remove the ring. Reheat the soufflé for 15 minutes, or until warmed through. Slice with a serrated knife and transfer to plates. Drizzle with the Armagnac syrup. Serve warm with the whole prunes and sweetened whipped cream.
Make Ahead The soufflé can be prepared through Step 5 earlier in the day.
This airy dessert needs only the grace note of a concentrated wine with similar flavors. Look for a fortified Pinot Gris or a late-harvest Viognier.