Step 1

Dissolve the espresso powder in the hot water; set aside.

Step 2

Line a 9x5-inch loaf pan with plastic wrap that overhangs all sides of the pan. Line the sides and the bottom of the pan with the lady fingers, standing up vertically around the sides of the pan. Tear small pieces of lady fingers and press into gaps in the bottom of the pan (see video).

Step 3

Fill a saucepan with 1 inch of water and bring to a simmer. Set a large metal bowl on top and add the egg yolks, sugar, rum, and salt. Add the espresso mixture. Whisk until the mixture thickens like custard. The mixture is ready when an instant read thermometer registers 160F. Remove from the heat and cool 5 minutes. Transfer to the bowl of an electric mixer and beat with the whip attachment until the bowl feels cool to the touch, about 5 more minutes.

Step 4

Beat 1 3/4 cups of the heavy cream on medium-high until slightly thickened. Add 3 tablespoons of the powdered sugar and beat until stiff peaks form. Fold the whipped cream into the beaten espresso custard mixture. Spoon the mixture into the lined loaf pan. Smooth the top and tap on the counter top to remove air bubbles. Fold in the plastic wrap and freeze until solid, about 4 hours or overnight.

Step 5

Beat the remaining cream on medium-high speed gradually adding the remaining 3 tablespoons of sugar. Add mascarpone a little at a time while beating. Whip to stiff peaks. Spread the top of the frozen semifreddo with the whipped mascarpone cream. Return to the freezer.

Step 6

Heat the heavy cream in a saucepan until steaming but not boiling. Add in chopped chocolate. Let stand one minute and then whisk together. Let cool until thickened yet still pourable, about 15-20 minutes.

Step 7

Remove the semifreddo from the pan from the overhanging plastic. Unwrap and place on a serving tray. Cover with chocolate ganache. Sprinkle on chocolate shavings, chocolate-covered espresso beans, and almonds. Serve immediately or return to the freezer until set. When the chocolate is set, cover in plastic wrap until ready to serve.