In a small bowl, combine the heavy cream, instant espresso powder, and unsweetened cocoa powder. Whisk until smooth.

In a large mixing bowl, beat the softened mascarpone, cream cheese, and sifted confectioners' sugar at medium-high speed until smooth (about two minutes). Pause to scrape down the sides of the bowl as needed.

Add the cream mixture, vanilla extract, and a pinch of kosher salt. Start mixing at low speed until the ingredients are just combined, then increase to medium-high and beat until the mixture is light and fluffy (about one more minute).

Spoon the dip into a serving bowl, dust with additional cocoa powder if desired, and serve with ladyfingers for dipping.