Step 1

Cook the Egg Mixture - In a medium heatproof bowl, add egg yolks, 2 tablespoons coffee liqueur, ¼ cup of sugar, and vanilla. Set the bowl on top of a saucepan filled with about 1-inch water. The bowl should not touch the water. Bring the water to barely a simmer and vigorously whisk until the mixture is foamy and reaches around 140ºF (60ºC) on a thermometer, about 5 minutes. Turn off the heat and take the bowl off of the pot.

Step 2

Add the Mascarpone - Add mascarpone cheese to the egg mixture and whisk until smooth.

Step 3

Whip the Heavy Cream - In a separate medium bowl, vigorously whisk the heavy whipping cream and ¼ cup sugar until medium peaks form. Gently fold ⅓ of the whipped cream mixture into the mascarpone mixture. Then add the remaining whipped cream, and fold until just combined.

Step 4

Assemble the Layers - In a large bowl, combine coffee and 3 tablespoons of coffee liqueur. Working one ladyfinger at a time, dip it into the liquid, about 2 seconds per side. Transfer to an 8-inch square baking dish. Dip just enough for the first layer.Spread half of the mascarpone mixture over the ladyfingers. Dip the remaining pieces, and arrange them on top of the cream layer. Then spread the remaining mascarpone evenly on top.

Step 5

Add Cocoa and Chill - Sprinkle some of the cocoa powder evenly over the baking dish. Clean the edges of the dish as needed. Cover with foil and refrigerate for at least 8 hours or up to 5 days.

Step 6

To Serve - Allow the tiramisu to sit at room temperature for 20 minutes before serving. Sprinkle with more dry cocoa powder if desired.