Step 1: Prepare the Coffee Mixture

1. Brew a cup of strong espresso or coffee and allow it to cool slightly.
2. Stir in sugar (if using), vanilla extract, and coffee liqueur. Mix well and set aside.

Step 2: Make the Mascarpone Cream

1. In a mixing bowl, beat the heavy whipping cream using an electric mixer until soft peaks form.
2. In a separate bowl, mix mascarpone cheese with powdered sugar and vanilla extract until smooth.
3. Gently fold the whipped cream into the mascarpone mixture, combining until smooth and fluffy.

Step 3: Assemble the Mini Tiramisu Cups

1. Break ladyfinger biscuits in half to fit into small serving cups or glasses.
2. Quickly dip each piece of ladyfinger into the coffee mixture (do not soak too long, or they will become too soggy).
3. Layer the dipped ladyfingers in the bottom of each cup.
4. Spoon a generous amount of mascarpone cream over the ladyfingers, spreading evenly.
5. Repeat with another layer of soaked ladyfingers, followed by another layer of mascarpone cream.
6. Smooth the top and lightly dust with cocoa powder.

Step 4: Chill and Serve

1. Cover the cups with plastic wrap and refrigerate for at least 4 hours (preferably overnight).
2. Before serving, add additional cocoa powder, chocolate shavings, or cocoa nibs for garnish.