1. Prepare the Crust:

1. Combine cooled coffee and coffee liqueur in a shallow dish. Set aside.
2. In a large bowl, beat egg yolks with sugar until pale and creamy. Add mascarpone and ground pistachios, mix until smooth.
3. In a separate bowl, beat egg whites until stiff peaks form. Gently fold into mascarpone mixture.
4. Quickly dip each ladyfinger into coffee mixture and layer in bottom of 8×8 inch dish.
5. Spread half of pistachio cream over ladyfingers. Repeat with another layer of dipped ladyfingers and remaining cream.
6. Cover and refrigerate for at least 4 hours or overnight. Dust with cocoa powder and garnish with pistachios before serving.