The dough for this recipe is adapted from King Arthur Baking Company.
Add all dough ingredients in the bowl of a stand mixer fitted with a dough hook. Use a silicone spatula or wooden spoon to roughly combine, and then turn the mixer on low.
Knead on low speed for 7-10 minutes, or until dough is smooth and stretch and passes the windowpane test.
Transfer the dough to a medium bowl that has been lightly coated with vegetable oil. Cover with plastic wrap and refrigerate overnight, or for at least 6 hours. (The dough will rise in the fridge.)
In the morning, remove the dough from the refrigerator and transfer it to a lightly floured work surface. Roll the dough out into a large-ish rectangle. (Mine was about 10 inches by 12 inches).
Spread a thin layer of chocolate hazelnut spread over the middle third of the dough rectangle. Fold the right third of the rectangle over the chocolate-coated middle third, like a business letter, and spread another thin layer of chocolate hazelnut spread on top. Fold the left third of the dough rectangle over this second chocolate layer, completing the "business letter fold."
Rotate the resulting long, thin rectangle 90 degrees, so that the longer side is facing you. Roll it out into a larger rectangle, about 6 inches in width.
Use a pizza cutter, bench scraper, or sharp knife to cut the rectangle into 4 long strips. Then cut each strip in half, to create 8 shorter strips.
Line a baking sheet or baking pan with parchment paper.
Roll each of the strips, cut side up, into a swirly roll, and transfer to the baking sheet. (I arranged them in a snake-like pattern, but go with whatever you fancy!) Cover with plastic wrap (I coat it with a bit of nonstick spray), and allow to rise at room temperature for about 45 minutes, until puffy.
Meanwhile, preheat the oven to 350 F.
Bake the rolls for 20-25 minutes, or until the tops are lightly brown and the interior is 195-200 F on an instant read thermometer.
Allow to cool slightly, and enjoy!