Bake cakes until tester inserted into center comes out clean, about 20 minutes. Cool in pans on rack.
PANNA COTTA: Place ½ cup water in small bowl. Sprinkle gelatin over; let stand until softened, about 10 minutes. Place both chocolates in large metal bowl. Combine cream, milk, sugar, and vanilla extract in large saucepan. Scrape in seeds from vanilla beans; add beans. Bring to boil, stirring until sugar dissolves; remove from heat. Add gelatin mixture to hot cream mixture; whisk to dissolve. Discard vanilla bean. Pour cream mixture over chocolates in large metal bowl; whisk until melted and smooth. Place bowl over larger bowl of ice water. Stir often until panna cotta mixture thickens like pudding, draining off water and adding more ice to larger bowl as needed, about 30 minutes. Remove smaller bowl from over ice water.
Pour half of panna cotta mixture over cake in 1 pan (mixture may drip down sides of cake). Freeze until firm, about 45 minutes. Keep remaining panna cotta mixture at room temperature.
Remove pan sides from second cake. Using large metal spatula, carefully slide cake onto panna cotta in first cake pan. Pour remaining panna cotta mixture over, filling pan completely. Cover tightly with foil and chill overnight.
DO AHEAD: Can be frozen for 2 weeks. Defrost overnight in refrigerator before continuing.
CHOCOLATE BAND: Line large baking sheet with foil. Place another large sheet of foil on work surface; top with waxed paper strips, spaced apart. Stir chocolate in medium bowl set over pan of simmering water until melted and smooth. Pour half of melted chocolate down center of each waxed paper strip. Using small offset spatula, spread chocolate to cover strips evenly and completely (some chocolate may extend beyond edges of paper strips). Using fingertips, lift chocolate-coated strips and place on foil-lined sheet. Refrigerate until chocolate just begins to set but is still completely flexible, about 2 minutes.
Cut around pan sides to release assembled cake; remove pan sides. Using fingertips, lift 1 chocolate strip from foil. Wrap band around cake, chocolate side in, lining up 1 long edge with bottom of cake (band will be higher than cake and only go about halfway around). Repeat with second band, pressing band onto uncovered side of cake and arranging so ends meet. If bands overlap, trim any excess paper and chocolate. Using fingertips, press top edge of band in toward cake, forming slight ruffle. Chill until chocolate sets, at least 5 minutes. Gently peel off waxed paper. Chill cake.
DO AHEAD: Can be made 1 day ahead. Cover with cake dome and keep chilled.Shopping Tip: The Best ChocolateIf ever there was a time to splurge on the finest-quality chocolate, it would be for this cake and its panna cotta filling. Panna cotta is smooth and creamy, and superior chocolate gives it a silky texture that lesser-quality chocolates just can’t provide. If brands like Lindt or Perugina are not in the baking aisle at your supermarket, check the candy aisle.
These cakes can be completely assembled the day before, then quickly baked before serving. Even though it goes against all the traditional rules of baking cakes, be sure to remove these from the oven while the centers are still soft and gooey—or “molten.” Once the tops of the cakes are broken with a spoon, the soft centers become the sauce. Makes 8
Ice Cream
1 pint vanilla ice cream, softened
2 tablespoons chopped crystallized ginger
1 tablespoon dark rum
Cakes
14 ounces bittersweet or semisweet chocolate (do not exceed 61% cacao), chopped
1¼ cups (2½ sticks) unsalted butter
2 teaspoons ground coriander
2 teaspoons ground cardamom
1 teaspoon ground cinnamon
½ teaspoon ground cloves
½ teaspoon freshly ground white pepper
6 large eggs
6 large egg yolks
2 teaspoons vanilla extract
3 cups powdered sugar
1 cup unbleached all purpose flour
Additional powdered sugarCrystallized ginger strips
ICE CREAM: Place softened ice cream in medium bowl. Using plastic spatula, fold ginger and rum into ice cream. Transfer to airtight container. Freeze ice cream mixture until firm, about 4 hours.
DO AHEAD: Can be made 1 day ahead. Keep frozen.
CAKES: Generously butter eight ¾-cup soufflé dishes. Stir chocolate, butter, coriander, cardamom, cinnamon, cloves, and white pepper in heavy medium saucepan over low heat until melted and smooth. Cool slightly. Whisk eggs, egg yolks, and vanilla in large bowl to blend. Whisk in powdered sugar, then chocolate mixture, then flour. Transfer batter to prepared dishes, filling to top.
DO AHEAD: Can be made 1 day ahead. Cover and refrigerate.
Preheat oven to 425°F. Bake cakes until batter has risen above sides of dish, top edges are dark brown, and center is still soft and runny, about 15 minutes (or about 18 minutes for refrigerated batter). Run small knife around cakes to loosen. Allow cakes to stand in dishes 5 minutes. Place small plate atop 1 dish with cake. Using oven mitts or pot holders, hold plate and dish firmly together and invert, allowing cake to settle onto plate. Repeat with remaining cakes. Sift additional powdered sugar over cakes. Top with crystallized ginger strips. Serve cakes with rum-ginger ice cream.
To avoid overbaking the pudding in the middle of these cakes, start checking early for doneness—unlike most other traditional cakes, the tester should come out with wet batter attached. You can make your own superfine sugar by pulverizing granulated sugar in a food processor until it is finely ground; but this recipe can also be made with regular sugar. Makes 6
6 ounces bittersweet or semisweet chocolate (do not exceed 61% cacao), chopped
½ cup (1 stick) unsalted butter, cut into 4 pieces
3 large eggs
3 large egg yolks
⅓ cup superfine sugar or regular sugar
¼ cup unbleached all purpose flour
1¼ teaspoons peppermint extract
¼ teaspoon saltPowdered sugarPeppermint stick ice cream or mint chocolate chip ice creamFresh mint leaves
Preheat oven to 375°F. Lightly butter six ¾-cup ramekins or custard cups. Stir chocolate and butter in heavy small saucepan over low heat until melted and smooth. Remove from heat and cool slightly.
Using electric mixer, beat eggs, egg yolks, and sugar in large bowl until slightly thickened, about 5 minutes. Add flour and beat until blended. Add chocolate mixture, peppermint extract, and salt; beat just until incorporated. Divide chocolate mixture among prepared ramekins. Place ramekins on baking sheet.
DO AHEAD: Can be made 1 hour ahead. Let stand at room temperature.
Bake cakes until edges are set but center looks shiny and still moves slightly when ramekins are gently shaken and tester inserted into center comes out with wet batter attached, about 11 minutes. Run small knife around each cake to loosen.