8 ounces bittersweet chocolate, chopped, plus shavings for garnish (optional)
1 1/2 sticks (6 ounces) unsalted butter
3 large eggs, plus 3 large egg yolks, at room temperature
1/2 cup sugar
1/4 cup cake flour
1/2 cup heavy cream
1/2 vanilla bean, split and seeds scraped
2 tablespoons light brown sugar
1/2 teaspoon finely grated lemon zest
1 cup mascarpone (8 ounces)
1 teaspoon fresh lemon juice
About 1/2 cup brandied cherries or kirsch-soaked sour cherries
Preheat the oven to 375°. Coat six 6-ounce ramekins with butter, and dust lightly with flour. Set the ramekins on a sturdy baking sheet. In a microwave-safe bowl, melt the chocolate with the butter; let cool.
In the bowl of a standing electric mixer fitted with the whisk, beat the eggs, yolks and sugar on high speed until pale and fluffy, about 4 minutes. Using a rubber spatula, gently fold in the chocolate, then fold in the cake flour just until no streaks remain.
Spoon the batter into the prepared ramekins and bake for 15 minutes, until the cakes have risen, the tops are dry and the centers are slightly jiggly. Let stand for 5 minutes.
In a bowl, beat the cream with the vanilla seeds, brown sugar and lemon zest until soft peaks form. Add the mascarpone and lemon juice and beat until blended.
Run the tip of a small knife around each cake to loosen it, then unmold onto plates. Spoon the mascarpone cream onto the cakes and garnish with the brandied cherries and chocolate shavings.