1/ Prepare the coffee: Brew black coffee or espresso and let it cool to room temperature.
2/ Prepare the mascarpone: Remove the mascarpone cheese from the refrigerator to allow it to soften slightly.
3/ Separate the eggs: Separate the egg yolks and whites into two clean bowls.
4/ Whisk the egg yolks: Add the sugar to the bowl with the egg yolks and whisk with a hand whisk or electric mixer until pale and creamy. Add the mascarpone cheese to the mixture and mix until smooth.

5/ Whisk the egg whites: Add a pinch of salt (not listed) to the egg whites and whisk with a clean whisk or electric mixer until stiff peaks form.

6/ Combine mixtures: Gradually fold the whipped egg whites into the mascarpone mixture in two or three portions.

7/ Assemble the layers: Spread a thin layer of the mascarpone cream in the bottom of a dish.

8/ Dip the biscotti savoiardi: Pour the cooled coffee into a dish. Briefly dip both sides of the biscotti savoiardi into the coffee, ensuring they absorb some coffee but do not become too soggy. Arrange the soaked biscuits on top of the mascarpone cream.

9/ Repeat the layers: Spread another layer of mascarpone cream over the biscuits. Add another layer of coffee-soaked biscotti savoiardi, followed by a final layer of mascarpone cream.
10/Finish with cocoa powder: Sift unsweetened cocoa powder over the top layer of mascarpone cream to cover evenly.

11/ Chill and serve: Refrigerate the tiramisu for at least 3 hours (or overnight for the best flavor and texture) before serving.
