Step 1

Mix the espresso with the coffee liqueur; chill.

Step 2

Melt the chocolate with 1/2 cup cream over a double boiler; cool.

Step 3

Whip the remaining 1/2 cup cream (or 3/4 cup, but remember more cream will give volume but dilute the flavor of the mascarpone) until stiff.

Step 4

Using a hand-held whisk (a stand mixer will be too strong), whip the mascarpone with the sugar and rum until just mixed. Do not over whisk or the cheese will curdle. Fold the whipped cream into the cheese mixture. Chill until firm.

Step 5

If using a sponge cake, cut into 3 layers about 1 cm thick. I used to cut the cake into 1/2 cm layers and sandwiched them with chocolate ganache. The result was the best tiramisu ever, but was too much work because the thin sponge layers broke easily.

Step 6

Lay a layer of 10 sponge fingers into a glass dish or bowl (or a slice of sponge cake on a serving plate), spoon about 1/3 of the espresso over the fingers to soak. Spread 1/3 of the chocolate ganache over the cake and then spread 1/3 of the mascarpone mixture over. Repeat and end with a layer of mascarpone.

Step 7

Sieve a thick layer of choc powder over the tiramisu and/or garnish with choc shavings. Chill overnight or at least 12 hours.