Whip 3 cups heavy cream with 1/4 cup sugar until stiff peaks form. Set aside.
Whip egg yolks with 5 ounces sugar until thick and pale in color and about doubled in volume. The mixture should form thick ribbons when the beaters are lifted.
In small increments with the machine running, add mascarpone cheese to the egg yolk mixture. Add rum and cinnamon, being careful not to overmix.
Fold in a third of the mascarpone with the whipped cream. Then fold in the remaining mascarpone mixture in thirds.
Combine espresso, 1/4 cup sugar, coffee liqueur. Soak ladyfingers in espresso mixture.
Place three ladyfingers side by side on a serving plate. Top with cheese mixture. Repeat three more ladyfingers and more cheese. Dust with cocoa powder, trim edges and serve.Makes 6 to 8 Source: