For the carrot muffins, peel, wash and finely grate the carrots. Mix together the grated orange zest, hazelnuts and carrots.
Preheat the oven to 160 °C. Line a muffin tray with paper cups. Separate the eggs. Beat egg whites with salt and 50 g sugar until stiff.
Beat yolks, remaining sugar and orange juice until creamy. Stir in carrot mixture, fold in beaten egg whites and flour.
Pour the mixture into the muffin tins and bake for 30 minutes. Then let cool in the muffin tin.
Mix orange juice and jam and spread on the cooled carrot cakes. Mix powdered sugar with a little water until smooth and pour over the carrot muffins.