Preparation Steps

• In a heatproof bowl set over a saucepan of simmering water, whisk together the egg yolks and sugar until pale and slightly thickened. Cook, whisking constantly, for about 5-7 minutes, until the mixture is thick enough to coat the back of a spoon. Remove from heat and let cool slightly.
• In a separate bowl, beat the softened mascarpone cheese until smooth. Gradually fold in the cooled egg yolk mixture until well combined.
• In another bowl, whip the heavy cream with the vanilla extract until stiff peaks form. Gently fold the whipped cream into the mascarpone mixture until just combined.
• Fold in the finely ground pistachios. Cover the pistachio cream and refrigerate for at least 30 minutes.
• In a shallow dish, combine the cooled coffee and coffee liqueur (if using).
• Quickly dip each ladyfinger into the coffee mixture, ensuring they are moistened but not saturated. Arrange a single layer of dipped ladyfingers in the bottom of an 8x8 inch baking dish.
• Spread half of the pistachio cream evenly over the ladyfingers.
• Repeat with another layer of dipped ladyfingers and the remaining pistachio cream.
• Cover the tiramisu and refrigerate for at least 4 hours, or preferably overnight, to allow the flavors to meld and the ladyfingers to soften.
• Before serving, sprinkle the top with chopped pistachios.