To make your Sabayon base, add egg yolks and sugar in the top of a double boiler. Bring water to a boil then reduce heat to low, and cook for about 10 minutes, stirring constantly. Do not let it get too hot. Remove from the heat and whip yolks until thick and light yellow in color. Add Mascarpone cheese to whipped yolks and stir until combined. Set aside.

In your mixer fit with a whisk attachment, whip cream until stiff peaks form.

Gently fold the whipped cream in the mascarpone sabayon mixture and set aside.

Mix the cold espresso with the coffee liquor (or in my case, the Mocha flavored Kahlua) and dip the ladyfingers into the mixture just long enough to get them wet

Arrange the ladyfingers in the bottom of a 5 × 9 baking dish. I overlapped my cookies slightly. Next time, I'll double up the cookies for each layer.

Spoon half the mascarpone cream filling over the ladyfingers.

Add ladyfingers on top of the cream and cover with the remainder of the cream.

Refrigerate 4 hours or overnight.

Prior to serving, make ganache if desired.

Heat cream in microwave for 20 seconds. Pour over chocolate and stir. Re-heat in microwave at 70% power for 20 second intervals until melted. Stir until smooth.

Dust with cocoa and add ganache before serving.