I've just taken it out of the oven and it doesn't look too bad. However,
I think I used too much Nutella and next time it will only be a very
thin smear on each layer. I don't think my grandson will complain:-)

https://postimg.org/image/3tp16isfl/

The enriched dough recipe was for a fairly standard cinnamon bun and 2
different sources quoted the same proportions. Here is the recipe using
metric weights etc. google for cups.

450g AP flour
70g sugar
pinch of salt
180ml milk (full fat) IMO this is not enough!!
2tsp instant yeast
2 egg yolks
30g softened butter
Nutella

Method (I used a food processor - thankfully!)
Warm the milk for 30secs in the MW
Add the yeast and whisk to dissolve.
Put the flour sugar and salt in the FP and mix briefly.
Add the egg yolks and blitz to disperse.
With the motor running, add the milk mix in a steady stream to form a dough.
At this point I had to add extra milk as the all I had was a bowl full
of large crumbs. I added extra until it produced a dough then added the
soft butter and processed until it was incorporated.
With the extra milk I ended up with 852g of dough which I divided into
4x213g pieces that I kneaded into balls and put into separate oiled
bowls for the first rise.
After rising, I rolled each piece out into a 10" disc. And at this point
it is better to follow this youtube video:

https://www.youtube.com/watch?v=HwvYmBo_bN4

One can use other fillings such as cinnamon/sugar mix and there are
savoury versions too.
It looks somewhat difficult but it isn't and I'll probably make this
again with the help of my grandchildren.
Graham