Preheat the oven to 350°F (175°C). Grease and line a small loaf pan with parchment paper.
In a mixing bowl, whisk the Nutella, eggs, and vanilla extract until smooth. Add the salt and flour, stirring just until combined. Pour the batter into the prepared pan and smooth the top.
Bake for 17 to 20 minutes, or until the center is just set. Remove from the oven and let cool completely.
In a medium bowl, beat the heavy cream and cream cheese until smooth. Add the Nutella, powdered sugar, and pudding mix, then whip until light and fluffy.
Use a round cutter or a glass to cut 4-inch (10 cm) circles from the cooled cake. Layer the cake rounds with the Nutella cream, smoothing the sides for a clean finish. Place in the freezer for 10 minutes to firm up.
Drizzle the melted Nutella over the chilled cake, using a spoon or piping bag to create decorative swirls or heart shapes. Keep refrigerated until ready to serve.
RECIPE NOTES
For an extra touch, sprinkle the top with sea salt or chopped hazelnuts for added crunch.