Combine all the ingredients (except for the Nutella) in a mixing bowl or the bowl of a stand mixer. Mix and knead until a smooth, soft dough forms. Cover and set aside for 1 hour or until doubled in volume.
In the meantime, preheat to 375°F. Line a baking sheet with parchment paper.
Gently deflate the dough and on a lightly floured surface, roll it out into a 10″x12″ rectangle.; Spread Nutella evenly on the dough leaving a 1″ edge on all sides. Roll the dough into a tight roll and bring both the ends together. Lightly brush water on the ends and pinch them together.
Transfer it onto the baking sheet. Using a sharp knife, score the dough into 12 equal pieces. Gently spread the pieces a little bit.
Brush the top with water and sprinkle the remaining 1 tbsp of sugar.
Bake for 25~30 minutes, or until the top is golden. Remove onto a wire rack and let cool completely before digging in.