First, make a yeast dough from the above ingredients. To do this, heat the butter and milk to lukewarm and mix with the yeast. Then mix the yeast solution with flour, sugar and cardamom to a smooth dough. Cover and let rise in a warm place for about 40 minutes.

Meanwhile, cream the soft butter with sugar and cinnamon. Roll out the yeast dough into a rectangle and carefully coat with the mixture. Then roll up the dough from the long side and cut into 2cm thick slices. Place the slices with the cut surface facing upwards on a baking tray covered with baking paper. Cover and let rise for another 15 minutes. Preheat the oven to 190 degrees.

In the meantime, prepare the hazelnut crumble. Mix the flour, hazelnuts, sugar and vanilla sugar. Add the melted butter and knead the mixture well.

Finally, whisk the egg yolk with a little milk and brush the snails with it. Then add the crumbles.

Bake the cinnamon buns on the middle rack for about 20 minutes until golden brown