Peel the carrots and grate finely. Drain 100 g grated carrots on kitchen paper. Finely grind the nuts. Melt 60 g butter over a mild heat. Mix the flour, baking powder, sugar and nuts. Mix the egg with the hand mixer for 2 minutes until creamy. Add the buttermilk and melted butter one after the other and stir. Mix in the flour mixture and all of the shredded carrots with a spatula. Let it rest for 5 minutes. Preheat the oven to 190 degrees top / bottom heat.
Put the mixture with 2 tablespoons in 24 small piles on 2 baking sheets with baking paper. Bake one after the other in the hot oven on the middle rack for 15 minutes. Let cool down on the baking sheet.
Mix 50 g butter, 60 g powdered sugar and vanilla sugar with a hand mixer for 5 minutes until creamy. Stir in the cream cheese on a slow speed. Pour cream into a disposable piping bag, cut off the tip from the bag and sprinkle half of the biscuits with the cream on the flat side. Place the remaining biscuits on top and press lightly. Serve the finished whoopies dusted with the rest of the powdered sugar.