enough to fill 6 half-cup ramekins, or several more smaller cups
Using either a double boiler or simply a bowl set in a pan of simmering water, melt the chocolate, stirring occasionally. Remove from heat and let cool to room temperature. Sift in the maca powder, and stir to combine.
Place the tofu, chocolate + maca, vanilla, and salt in the work bowl of a food processor. Pulse to combine, then with the motor running, drizzle in the cooled espresso and purée until smooth. Pour into individual serving ramekins, cover with plastic wrap and refrigerate for at least 1 hour before serving.