• Brew espresso coffee: place in a wide shallow dish. Stir in alcohol of your choice (Marsala, rum, coffee liqueur, or amaretto) and set aside to cool.

For the pistachio butter

• Add shelled pistachios in the bowl of your food processor and process until finely chopped.  Add honey, vegetable oil and process until completely smooth and creamy, about 2 minutes.  Scoop into a bowl and set aside.

For the mascarpone cream

• Separate the eggs and place the whites and yolks in separate bowls. Place the bowl with the egg whites in the fridge to keep cool for whipping them later.
• Prepare a double boiler:  Combine the egg yolks with sugar in a bowl and place over a small sauce pan with water simmering in it. The simmering water should not touch the bottom of the bowl.
• Whisk until the mixture is creamy and pale and forms ribbons when you lift the whisk, about 3 minutes. Let it cool.
• Meanwhile, whisk the egg whites until stiff peaks form. You can do this by hand or with an egg beater.
• When the egg yolk mixture has cooled, stir in mascarpone cheese until smooth.  Gently fold in half the egg whites.  Stir in the other half. Add the pistachio butter and stir until completely incorporated. 

To assemble:

• Spread a thin layer of mascarpone cream on the bottom of a rectangular dish (approx   x  ). You can skip this step if you wish, I just like something on the bottom for the cookies to stick to.
• Dip Savoiardi cookies in the cooled espresso coffee, turning once to soak each side and place in an even layer in the dish. 
• Spread half the mascarpone-pistachio cream mixture over the cookies and gently spread the cream evenly using an offset spatula.  Dip more Savoiardi cookies to make a second layer of cookies over the cream. Spread the remaining mascarpone-pistachio cream over the cookies. 
• Dust lightly with cocoa powder and sprinkle with chopped pistachios.
• Place in the fridge for at least 6 hours or make the day ahead. Serve cold.