Combine the yeast, honey, and water. Let the mixture bloom for 10 minutes until yeast is puffed up and bubbly.

Add mixture into a stand mixer, along with 1 cup flour, egg and egg yolk. Mix until batter forms, then let rest for 15 minutes.

Add the remaining flour and salt into the batter, knead the dough for 10 minutes on low speed using the hook attachment. Cover the dough and let rise for 2 hours in a warm space.

On a floured surface, knead the dough by hand for 3 minutes. Roll the dough into a thin rectangular shape. Spread the nutella on half of the rectangular dough. Fold the other half right over, to cover all the chocolate. Roll the dough a little to flatten out more, then cut the dough into 1 inch wide strips. Twist the strips of dough and wrap around into a circle shape. Place on a parchment paper lined pan and allow to rise for 45 minutes in a warm space.

Preheat the oven to 350F.

Using the 1 egg white, brush on top of all the buns until fully covered. Bake the buns for 20-25 minutes or until the tops are golden brown. Allow to cool for 10 minutes.

Mix the powdered sugar, milk, and vanilla extract until smooth (you may need to add more milk depending on what icing consistency you want). Drizzle on the cooled buns. Allow buns to rest for 5 minutes for icing to harden before serving.