Preheat your oven to 400°F (200°C).
In a large mixing bowl, whisk together flour, baking powder, sugar, baking soda, and salt.
Add cold unsalted butter to the dry mixture and work it in until it resembles coarse crumbs.
Pour in the buttermilk and stir gently until just combined.
Fold in Nutella gently until swirls are visible.
Drop generous amounts of dough onto a lined baking sheet, leaving space between each biscuit.
If desired, sprinkle sea salt on top of each biscuit before baking.
Bake for about 12-15 minutes or until golden brown on the edges.
Let cool on the baking sheet for a few minutes before transferring to a wire rack.
