I take much pleasure in making various desserts even though I don't really have a sweet-tooth. IMO there are several technical aspects that one should pay attention to when making a good tiramisu. However, I would normally approach this with a chef’s instinct, rather than being a stickler for precise quantities of ingredients. That being the case I have arrived at a definitive record of how I make tiramisu.
The important principles of tiramisu:
- It should use only mascarpone. Some recipes use whipped cream to bulk it out, but this mutes the flavour of the mascarpone.
- It should use raw eggs. I understand some may be uncomfortable with this but they are essential in providing the right texture.
- It should use cocoa powder for the topping, and this is best applied before serving.
Crema di mascarpone:
- 500g mascarpone
- 100-120g sugar (to taste)
- 4 large eggs (UK large eggs)
- 3 tablespoons Marsala wine
- approx. 40 Savoiardi (Ladyfinger) biscuits
- 6-8 strong espresso shots
- sugar and Kahlúa to taste
Prepare the espresso in advance, add Kahlúa and a little sugar and enough water to make approx.
400ml 320ml*. Set aside. Next make the crema di mascarpone which will require an electric mixer many bowls and at least one spatula. First carefully separate the eggs into yolks in one bowl and whites in another. At this stage add a small pinch of salt to the whites.
Next make a cold zabaglione (sabayon) - Mix egg yolks, sugar and Marsala wine and use an electric mixer with a whisk attachment to beat on a medium to high speed until very thick. This will take at least ten minutes - stop at intervals to scrape down the sides of the bowl to ensure a homogenous mix. The prolonged mixing time will ensure the sugar has dissolved and wine is fully emulsified. Transfer the mixture into another bowl and set to one side.
Next remove mascarpone from the fridge, empty into a large bowl (this will occupy the final mixture) and work it a little just to loosen it. Separately, using an electric mixer and the whisk attachment whip the egg-whites until "stiff peaks". This is another crucial stage; while the whites at "soft peaks" still look foamy at the "stiff peak" stage the whites will look smoother. A good sign is the whisk will leave a trailing mark in whites and the top sides will taper in. Don't over mix as the water within the egg whites will leech out. It is equally important that they are not under worked either as we need a strong structure that stiff-peak egg whites will provide.
Lastly for the crema di mascarpone; the sabayon, whipped egg whites and mascarpone are carefully folded together. There are varying ways to do this but generally it is easiest to mix-down, i.e., start with the stiffest mixture and loosen it. To do this add part of the sabayon to the mascarpone and mix until homogenous. Then add the remaining sabayon in stages folding carefully to retain as much air as possible. It should feel loose and aerated. Next add the whites, again in stages being careful to fold them in gently to avoid knocking out any air but ensuring there are no unmixed parts. This gets easier with practice.
Finally construct the tiramisu - Briefly submerge the ladyfinger biscuits in the cooled coffee mixture and layer them. Alternate with the crema di mascarpone and smooth the top with a palate knife or spoon. Cover with plastic film or foil and leave to set overnight in the fridge - at least 8 hours.
Cut pieces and dust with cocoa powder to serve.
*Updated based on feedback.