Brew the coffee and leave it to cool.
Separate the egg yolks from the whites and place in a heatproof bowl with the sugar. Create a steam bath by placing the bowl over a pan filled with water, ensuring it doesn't touch the water. Cook over medium heat, stirring constantly with a whisk.
Cook until you get a creamy, light and airy mixture and the sugar has melted.
Leave the yolk cream to reduce to room temperature.
Using a mixer, fold the mascarpone cream cheese into the yolk cream, spoon by spoon! You will get a very smooth cream.
Finally, add the pistachio paste to the cream. Mix until smooth!
Dip the ladyfingers in coffee and place them in a tray/pan, leaving no space between them. Spread half the mascarpone and pistachio cream over the top. Layer coffee-dipped ladyfingers over the top and spread the other half of the cream over it.
Cover the pan with plastic wrap and refrigerate for at least five hours.
Just before serving, sprinkle a generous layer of coarsely chopped pistachios on top and slice with a thin-bladed knife. Enjoy!