Knead all the dough ingredients to form a smooth dough and then chill for 30 minutes.
Briefly toast the hazelnuts in a pan without adding any fat. Then mix with sugar and whipped cream. Beat the egg whites until stiff and fold carefully into the nut mixture.
Preheat the oven to 180 ° C.
Roll out the dough thinly on a floured work surface and brush with the nut mixture. Then divide into squares of 15 cm each and roll into croissants. Place on a baking sheet lined with baking paper.
Put in the hot oven and bake for about 30 minutes.
Tip: It also looks nice when you sprinkle the croissants with powdered sugar at the end.