#### 1. Make the mascarpone filling:
- In a mixing bowl, whisk the egg yolks and sugar together until pale and creamy, about 2–3 minutes.
- Add the mascarpone cheese and mix until smooth.
- In a separate chilled bowl, whip the heavy cream to stiff peaks.
- Gently fold the whipped cream into the mascarpone mixture in batches, being careful not to deflate the cream.
#### 2. Prepare the coffee soak:
In a shallow dish, combine the brewed coffee and coffee liqueur (if using).
#### 3. Assemble the tiramisu:
- Quickly dip each ladyfinger into the coffee mixture, ensuring they're saturated but not soggy. Arrange them in a single layer in the bottom of your baking dish.
- Spread half of the mascarpone filling evenly over the ladyfingers.
- Add another layer of soaked ladyfingers and spread the remaining mascarpone filling on top.
#### 4. Chill:
Cover the dish with plastic wrap and refrigerate for at least 6 hours, preferably overnight, to allow the flavors to meld.
#### 5. Serve:
Before serving, use a fine mesh sieve to dust the top generously with cocoa powder. Slice and serve chilled.