- 2/3 cup all purpose flour
- 3 tablespoons unsweetened cocoa powder (preferably Dutch-process)
- 1/2 cup powdered sugar
- 1/4 cup (1/2 stick) unsalted butter, room temperature
- 3 large egg yolks
- 1/2 cup plus 1 tablespoon sugar
- 3 tablespoons water
- 2 teaspoons light corn syrup
- 1/4 teaspoon fresh lemon juice
- 1/3 cup heavy whipping cream
- 1 tablespoon unsalted butter
- 1 cup heavy whipping cream
- 1 tablespoon light corn syrup
- 3 whole star anise
- 4 1/2 ounces bittersweet (not unsweetened) or semisweet chocolate, coarsely chopped
- 2 tablespoons (1/4 stick) unsalted butter, room temperature
- 1 ounce bittersweet (not unsweetened) or semisweet chocolate, finely chopped
- 4 teaspoons (generous) plus 2 tablespoons chopped lightly salted roasted cashews
- 1/4 cup sugar
- 2 tablespoons water
- 1/2 cup strained orange juice
- 1 2-inch piece peeled fresh ginger, grated, pressed through garlic press to extract 1/2 teaspoon juice
- 1/2 vanilla bean, split lengthwise in half
- 3 tablespoons unsalted butter
- 2 tablespoons (packed) golden brown sugar
- 1 large banana, sliced
- Sift flour and cocoa into small bowl. Using electric mixer, beat powdered sugar and butter in medium bowl until well blended. Beat in flour mixture. Beat in egg yolks 1 at a time. Gather dough into ball; flatten into disk. Chill at least 1 hour and up to 1 day. Soften slightly at room temperature before rolling out.
- Preheat oven to 375°F. Roll out dough on floured surface to 1/8-inch thickness. Using 5-inch-diameter plate or bowl as guide, cut out rounds. Reroll dough scraps if necessary to form four 5-inch rounds total. Press each dough round onto bottom and up sides of 4 1/4- to 4 1/2-inch-diameter tartlet pan with removable bottom. Pierce crusts all over with fork. Freeze crusts 10 minutes. Bake until firm to touch and beginning to pull away from sides of pans, about 15 minutes. Cool crusts completely in pans on rack.
- Combine sugar and next 3 ingredients in heavy small saucepan. Stir over medium heat until sugar dissolves. Increase heat and boil without stirring until deep amber color, occasionally brushing down sides of pan with wet pastry brush and swirling pan, about 7 minutes. Remove from heat; add cream (mixture will bubble vigorously). Stir over low heat until any caramel bits dissolve and caramel is smooth. Whisk in butter. Set aside.
- Bring cream and corn syrup to boil in heavy small saucepan. Add star anise; remove from heat. Cover; let steep 15 minutes. Discard star anise. Return mixture to boil. Remove from heat. Add 4 1/2 ounces coarsely chopped bittersweet chocolate and butter; whisk ganache topping until smooth.
- Stir 1 ounce finely chopped bittersweet chocolate in top of double boiler set over simmering water until melted. Brush inside of each crust with melted chocolate, then sprinkle each with 1 generous teaspoon chopped cashews. Spoon caramel filling over nuts in crusts (about 2 tablespoons for each). Chill tartlets until caramel sets slightly, about 30 minutes.
- Rewarm chocolate ganache topping just until pourable, if necessary. Spoon chocolate ganache atop caramel filling. Refrigerate just until ganache sets, about 45 minutes, then let tartlets stand at room temperature. (Can be made 1 day ahead. Cover tartlets loosely and let stand at room temperature.)
- Stir 1/4 cup sugar and 2 tablespoons water in heavy small saucepan over low heat until sugar dissolves. Increase heat and boil without stirring until medium (not deep) amber color, occasionally brushing down sides of pan with wet pastry brush and swirling pan, about 5 minutes. Remove from heat; slowly add orange juice and 1/2 teaspoon ginger juice. Scrape in seeds from vanilla bean. Return mixture to boil, stirring until any caramel bits dissolve. Boil until sauce is slightly syrupy and reduced to 1/4 cup, about 4 minutes. (Can be made 1 day ahead. Cover; let stand at room temperature. Rewarm over low heat just until pourable.)
- Preheat oven to 450°F. Melt butter in heavy small saucepan over low heat. Add brown sugar; whisk until blended, about 1 minute. Add banana slices and toss to coat. Transfer banana mixture to small baking sheet. Bake until bananas begin to brown slightly around edges and sugar mixture bubbles, about 4 minutes.
- Remove sides from tartlet pans. Place tartlets on plates. Drizzle ginger caramel sauce around tartlets. Arrange banana slices alongside. Sprinkle with remaining 2 tablespoons cashews and serve.
- Brown star-shaped seedpods sold at Asian markets, at specialty foods stores, and in the spice section of some supermarkets