Preheat the oven to 180°C and place cupcake liners in the cupcake mold.
In a mixing bowl, beat the eggs, granulated sugar, vanilla sugar, and salt on medium-high speed for two minutes until creamy. Gradually pour in the sunflower oil and mix until fully absorbed. Sift the baking powder, flour, and cocoa powder together, then add to the batter and mix on low speed. Finally, mix in the milk..jpg?x26845)
Use a spatula to scrape along the sides and bottom of the bowl, ensuring the batter is well-mixed..jpg?x26845)
Spoon about two full tablespoons of batter into each cupcake mold (approximately one full ice cream scoop per mold).
Bake the cupcakes in the preheated oven for 20 to 30 minutes, or until a toothpick inserted into the center comes out clean. Allow the cupcakes to cool completely on a wire rack.
Sift the powdered sugar and cocoa powder into the mascarpone. Beat on high speed for about two minutes until smooth and free of lumps.
Beat the heavy cream at high speed for about a minute. Cover the bowl with aluminum foil and refrigerate for 30 minutes to allow the cream to stiffen.
Transfer the chocolate cream into a piping bag and pipe decorative swirls of cream onto the cooled cupcakes.