Combine the flour, salt, sugar, yeast, milk and eggs in a stand mixer. Mix well for about 10 minutes until thoroughly combined.
Slowly add the butter and mix for another 5 to 8 minutes or until well combined.
When ready, transfer the dough to a large greased bowl, cover with a towel and leave in a warm environment for 2 hours or until volume becomes double
Take the dough and roll it on a flour-dusted surface into a 70 x 40 cm rectangle.
Spread the hazelnut filling evenly using a spatula and roll it into a tight log of about 13-inch.
Put the log into the freezer for about 10 minutes
Transfer to a cutting board and cut into 2 equal halves using a serrated knife. Cut the logs in half lengthwise the plait the halves: Criss-cross one half, cut side down, on top of the other half, forming an X.
Place into lined loaf pan and cover with a clean towel or cling film. Let the loaves rest for 1 hour
Preheat the oven to 180°C transfer to the preheated oven and bake for 35 to 40 minutes or until golden.
When ready, remove from oven, leave to rest for some time, then slice and serve.