Combine the egg yolks and castor sugar in a metal mixing bowl

Place the mixing bowl over a saucepan with boiling water and whisk the mixture continuously using a hand-held metal whisk till it resembles a pale yellow foam (this technique is called a bain-marie, and the mixture is called a sabayon).

When the sabayon is ready, take it off the bain-marie and let cool for 8 to 10 minutes.

While the sabayon is cooling, whip the cream and sugar together till firm. You can use an electric mixer for this.

Mix the sabayon into the whipped cream till well incorporated.

Add the mascarpone to the above mixture and fold in gently. Its best not to use an electric mixer for this. Fold it in so that no lumps are left. Set aside.

In a flat dish, mix the espresso and coffee liqueur. If you don't have an espresso machine, you can use instant espresso powder to make the required amount of coffee (OR do what i did and just get 3 espressos to go from your nearest Starbucks :P)

Dip the Savoiardi biscuits (only ONE long side facing down) in the espresso-liqueur for 1-2 seconds.

Place the biscuits in the dish with dipped side facing upwards. This way, the liquid will seep through till the bottom and soak the whole biscuit.

Complete one layer in the bottom of the dish using half the biscuits. You may break the biscuits to fit them into the edges, if so required.

Spread half the sabayon-cream-mascarpone mixture over the biscuit layer.

Use the remaining biscuits and coffee and make a second layer over the cream.

Spread the remaining sabayon-cream-mascarpone mixture over the second layer.

Dust the top lightly with the chocolate powder and cinnamon powder (I used drinking chocolate powder here). Use a fine sieve for this.

Serve into individual dessert plates. Enjoy!