Beat the double cream plus sugar until its stiff.
Fold in the mascarpone cheese and add in vanilla extract.
Dip the ladyfingers in the brewed coffee and lay them on the bottom of the tin/dish.
Apply the cream mixture to the top of the ladyfingers.
Repeat the process of laying ladyfingers and filling with the cream until the layers fill your tin/dish.
Refrigerate your tiramisu for at least one hour to 24 hours.
Dust it with cocoa before serving.
Serve it cold.