This is a perfect recipe for people who have never used phyllo. Some people make it sound as though if you break a sheet the whole dish is broken. Sheets can be broken and it's still "all good" and elegant.
Measure Nutella, corn syrup, and cinnamon sugar in measuring cups.
Set aside the measuring cups (with the ingredients still in them).
Melt butter and set aside with a pastry brush in it.
Unroll 1 sleeve of defrosted phyllo dough on work space.
Grease a square baking pan with butter.
Now pick up a sheet of phyllo dough and put it into the bottom of the pan (some will lay over the edge of pan so just butter it and stuff the thing in the pan, no big deal.).
Try to work fast because it's easy.
Use up 5 of the sheets this way.
Layer the next 5 sheets by sprinkling cinnamon sugar on top of the butter.
Put a sheet down and butter it.
Next, put a sheet down and brush it with butter and while holding down the phyllo sheet spread all of the Nutella on the sheet (if the phyllo moves around and your getting uptight soften it in the microwave).
Don't worry about getting it perfectly smooth and even.
Use the rest of the sheets by alternating buttered sugar cinnamon layers and buttered corn syrup drizzled layers.
When doing the corn syrup, use the amount you think you would like (you might want less or more than the said amount).
Brush the top with butter and sprinkle cinnamon sugar and drizzle a tiny bit of corn syrup.
Cook in oven on the bottom rack (to be sure that the bottom layers get cooked) for about 9 minutes or until the top layer is nice and brown.
Cut and eat !
This dessert's quality is compromised after a couple hours so you really shouldn't plan on storing it.