- 2½ cups strong black coffee, room temperature
- 1½ tablespoons instant espresso powder
- 9 tablespoons dark rum
- 6 large egg yolks
- 2/3 cup sugar
- 1/4 teaspoon salt
- 1½ pounds mascarpone cheese (cold) – do not soften to room temperature
- 1/3 cup heavy cream for adding to yolks
- ¾ cup heavy cream (cold) for whipping
- 14 ounces hard ladyfingers* (42 to 60 depending on size)
- 3½ tablespoons unsweetened cocoa powder
- 5 ounces semisweet or bittersweet chocolate, grated
- Stir coffee, espresso powder and 5 tablespoons rum in a wide bowl or baking dish until espresso is dissolved; set aside. For a less potent rum flavor use only 2½ tablespoons rum.
- In a medium heatproof mixing bowl, beat egg yolks with an electric mixer equipped with a whisk attachment at low speed just until combined.
- Add sugar and salt and beat at medium–high speed until mixture is pale yellow, 1½ to 2 minutes, scraping down sides of bowl with rubber spatula once or twice.
- Add 1/3 cup cream to yolks and beat at medium speed until just combined, 20 to 30 seconds; scrape bowl.
- Set bowl with egg mixture over medium saucepan containing 1–inch of gently simmering water; cook, constantly scraping along bottom and sides of bowl with a heatproof spatula, until mixture coats the back of a spoon and registers 160 degrees on an instant-read thermometer, 4 to 7 minutes.
- Remove from heat and stir vigorously to cool slightly, then set aside to cool to room temperature, about 15 minutes.
- Whisk in, by hand, the remaining 4 tablespoons rum until well combined.
- Using the electric mixer fitted with whisk attachment, at medium speed, beat in the mascarpone cheese until no lumps remain, 30 to 45 seconds.
- Transfer mixture to a large bowl and set aside.
- Pour ¾ cup heavy cream into the now empty medium bowl, replace the whisk attachment with beaters, and beat at medium speed until frothy, 1 to 1½ minutes.
- Increase speed to high, and beat until cream holds stiff peaks, 1 to 1 ½ minutes longer.
- Using a rubber spatula, fold one–third of whipped cream into mascarpone mixture to lighten, then gently fold in remaining whipped cream until no white streaks remain. Set mixture aside.
- Working one at a time, drop about half the ladyfingers into the coffee mixture, quickly roll, remove and transfer to a 13x9–inch pan, arranging in a single layer. Break or trim ladyfingers as needed to fit neatly into dish.
- Spread half the mascarpone mixture over ladyfingers; spread mixture smoothly and evenly to the corners and sides of the pan.
- Place 2 tablespoons cocoa in fine-mesh strainer and dust evenly over mascarpone. Sprinkle with half the grated chocolate.
- Repeat all layers once with remaining ingredients.
- Carefully wipe edges of the dish with a dry paper towel. Cover with plastic wrap, and refrigerate for 6 to 24 hours.
- Cut into pieces and serve chilled.
Note: If only soft ladyfingers are available, preheat oven to 350 degrees, arrange ladyfingers in a single layer on baking sheet, and bake until golden and crisp, 8 to 10 minutes. Cool on wire rack before using.
Yields: 10–12 servings