
Brew strong espresso and let it cool slightly. In a shallow dish, mix the cooled espresso with the coffee liqueur (if using).
In a large bowl, whisk together the mascarpone cheese, sugar, and vanilla extract until smooth and creamy. In a separate bowl, whip the heavy cream until stiff peaks form.
Gently fold the whipped cream into the mascarpone mixture until well combined. Be careful not to overmix.
Quickly dip each ladyfinger into the espresso mixture, ensuring they are soaked but not soggy. Arrange a layer of soaked ladyfingers in the bottom of a baking dish.
Spread half of the mascarpone mixture evenly over the ladyfingers. Sprinkle a layer of cocoa powder over the cream.
Repeat layers with the remaining ladyfingers, mascarpone mixture, and cocoa powder. Ensure the top layer is cocoa powder.
Cover the tiramisu with plastic wrap and refrigerate for at least 4 hours, or preferably overnight, to allow the flavors to meld together.
Before serving, dust the top with additional cocoa powder. Cut into squares and serve chilled. Enjoy!