Tiramisù Icebox Cake

• espresso, double shots
• sugar, for coffee syrup
• salt, for coffee syrup
• Marsala wine, for coffee syrup
• Marsala wine, for zabaglione
• gelatin, for zabaglione
• sugar, for zabaglione
• salt, for zabaglione
• egg yolk
• mascarpone cheese, cold, fridge temperature
• heavy cream, cold, from fridge
• sugar, for whipped cream
• xanthan gum, for whipped cream stabilization
• ladyfinger cookies, 6 per layer, 3 layers; bottom matte side dipped in syrup
• cocoa powder, for dusting top

Preparation

1. Step 1 · 145°F / 63°C

   0:56
   Prepare the coffee syrup by combining four double shots of espresso with sugar, a little salt, and Marsala wine. The Marsala adds caramel notes and fruity flavor. Set aside until ready to soak the ladyfingers.
2. Step 2 · 145°F / 63°C · 10 minutes

   1:43
   Set up a bain-marie with about 1 quart of water in a 3-quart pot. Add Marsala and gelatin to a bowl and whisk until dissolved. Add sugar, salt, and six egg yolks. Cook over the steam, whisking gently at first to keep the mixture moving without incorporating too much air. As it thickens, whisk more vigorously. Scrape down the sides periodically. Cook until the zabaglione reaches 145°F, is very ribbony, and has increased significantly in volume. Remove from heat and let rest for 10 minutes to allow temperature to drop before folding into mascarpone.
3. Step 3 · 90°F / 32°C

   5:15
   Place cold mascarpone in a bowl and spread it out to create surface area. Do not beat the mascarpone as it can warm up and break. Fold in the warm zabaglione in three stages, adding about a third at a time. The temperature difference (mascarpone from fridge, zabaglione around 90-95°F) will help soften the mascarpone. Continue folding until mostly combined, preserving the air whipped into the zabaglione. A few small lumps are acceptable.
4. Step 4 · 145°F / 63°C

   7:06
   Start with very cold heavy cream from the fridge. Combine xanthan gum with sugar to help disperse the xanthan evenly and prevent clumping. Add to the cold cream and whip to medium peaks—stop before reaching stiff peaks since the cream will be further agitated during folding and piping, which will whip it more. The xanthan hydrates and makes the cream extra silky, resembling Italian meringue.
   Doneness — medium peaks
5. Step 5 · 145°F / 63°C

   8:29
   Fold the whipped cream into the mascarpone mixture in three stages, starting with about a third. Hold the bowl at a 45° angle, scoop under, and lift over to fold. The mixture will develop a beautiful marshmallow taffy texture. Add the remaining whipped cream and fold until most streaks are gone. Load approximately 300 grams into a piping bag for each of the three layers.
6. Step 6 · 145°F / 63°C

   9:48
   Line a Pullman loaf pan with parchment paper, leaving overhang to act as a sling. Dip the matte bottom side of each ladyfinger into the coffee syrup and place upside down in the pan, spacing them a millimeter or two apart to allow for expansion. Use 90g of syrup for six ladyfingers. After dipping, gently pour remaining syrup over each cookie to ensure even absorption. Pipe the mascarpone cream into all corners first, tamp down to remove air pockets, then spread an even layer. Give the pan a couple firm taps to settle the cream.
7. Step 7 · 145°F / 63°C · 8 hours

   11:37
   Repeat the layering process: soak another layer of ladyfingers in coffee syrup, place in pan, and spread with mascarpone cream. Add a third layer of soaked ladyfingers and finish with a final top layer of mascarpone cream. Smooth the top with an offset spatula or bowl scraper. Transfer to the refrigerator to rest for a minimum of 8 hours, preferably 24 hours. During this time, the coffee syrup continues to penetrate the ladyfingers completely, and the gelatin and fat firm up as the dessert chills, allowing for clean slicing without weeping.
8. Step 8 · 145°F / 63°C

   13:27
   Run a knife along the sides of the pan to release the tiramisu. Use the parchment sling to carefully lift it out. Slice between the cake and parchment to release completely. Dust the top generously with cocoa powder. For clean slices, soak a knife in hot water before each cut—the warm knife slices through the rich, high-fat dessert like butter, producing beautiful glossy portions that showcase the layered ladyfingers and cream.