Prepare the crepe batter. In a large mixing bowl, whisk together the eggs, sugar, and vanilla until well combined. Sift the flour and cocoa powder into the bowl, and whisk until the batter is smooth and lump-free. Gradually whisk in the milk, followed by the vegetable oil, mixing until fully incorporated.

Heat a non-stick skillet or crepe pan over medium heat and lightly grease it with oil or butter. Pour about 1/4 cup (60ml) of batter into the pan, swirling to coat the surface evenly. Cook on one side only for 1-2 minutes, or until the edges lift easily and the underside is lightly browned. Repeat with the remaining batter, stacking the cooked crepes on a plate to cool.

Make the filling. In a large bowl, beat together the mascarpone, whipping cream, vanilla extract, and sweetened condensed milk until smooth and fluffy. Chill the filling in the refrigerator until ready to use.

In a shallow bowl, combine the brewed coffee and rum.

Assemble the crepes. Spread an even layer of the mascarpone filling over a crepe. Dip two pieces of ladyfingers briefly into the coffee mixture, then place them on the crepe. Roll the crepe into a cylinder shape, enclosing the filling and ladyfingers.

Once you finish assembling the crepes, refrigerate them for at least 2 hours to set and allow the flavors to meld.

Before serving, slice each crepe in half and arrange on a serving plate. Dust with cocoa powder and serve with freshly brewed coffee or your favorite fruits for a delightful treat.