In a large bowl, whip heavy cream with 1/4 cup powdered sugar and vanilla extract until stiff peaks form. Set aside.
In a shallow dish, combine cooled coffee, 1 tablespoon matcha powder, and granulated sugar. Stir until sugar and matcha are dissolved.
In a separate bowl, beat softened cream cheese with remaining 1/4 cup powdered sugar until smooth. Gently fold in the whipped cream until well combined.
Quickly dip each ladyfinger into the coffee-matcha mixture, ensuring they are lightly soaked but not soggy.
Arrange a layer of soaked ladyfingers in the bottom of a serving dish.
Spread half of the cream cheese mixture evenly over the ladyfingers.
Dust with 1/2 tablespoon matcha powder.
Repeat layers: soaked ladyfingers, remaining cream cheese mixture, and dust with remaining 1/2 tablespoon matcha powder.
Cover the dish and refrigerate for at least 4 hours, or preferably overnight, to allow flavors to meld and tiramisu to set.
Before serving, dust the top with additional matcha powder, if desired.
Optional Tips: For a richer flavor, add 1-2 tablespoons of coffee liqueur (such as Kahlua or Tia Maria) to the coffee-matcha mixture. If ladyfingers are not available, substitute with sponge cake slices. For a vegan version, use coconut cream instead of heavy cream and a plant-based cream cheese alternative. Consider adding a thin layer of sweetened red bean paste (anko) between layers for an authentic Japanese touch.