• Prepare the Coffee Mixture. In a shallow dish, combine the cooled coffee and coffee liqueur (if using). Stir to mix and set aside.
• In a heatproof bowl, over a double boiler (a bowl set over simmering water) whisk the egg yolks, vanilla extract, and granulated sugar together until the mixture becomes pale and slightly thickened for about 3-4 minutes.
• Be careful not to overheat the egg mixture, as we’re just looking to gently warm it. You will know it is ready when you can’t feel sugar granules while rubbing a small amount between your fingers.
• When its ready, set it aside to cool completely.
• In a large mixing bowl, add the room temperature mascarpone cream and heavy cream, and mix with an electric hand mixer it until stiff peaks form.
• On low speed, gradually add the egg yolk mixture mixing constantly until smooth, creamy, and homogeneous.
• Add the cooled, melted dark chocolate to the mixture gradually, mixing constantly. Use a rubber spatula to scrape down the sides of the bowl to ensure everything is well incorporated.
• Dip the ladyfingers quickly in the coffee mixture (1-2 seconds) and lay them in an even layer in the 13 by 9-inch baking dish.
• Top the soaked ladyfingers with half of the mascarpone mixture and smooth it out with a spatula.
• Add another layer of the dipped ladyfingers. Top the ladyfingers with a thin layer of the mascarpone cream. Cover with plastic wrap and place in the fridge for at least 4 hours to allow the ladyfingers to soften.

Make the chocolate whipped cream

• In a cold large mixing bowl add the heavy whipping cream, sift the cocoa powder, and add the powdered sugar, and vanilla.
• Whip with an electric hand mixer or in a stand mixer for about 2-3 minutes or until stiff peaks form. Once stiff peaks start to form, your whipped cream is ready!
• Transfer the chocolate whipped cream into a piping bag with a round tip and make dollops of the cream all over the tiramisu. Generously top the tiramisu with plenty of cocoa powder and serve!