Preheat your oven to 350°F (175°C) and line an 8x8-inch metal baking pan with parchment paper, leaving an overhang.
In a large bowl, whisk the room-temperature eggs vigorously until pale and frothy.
Add the Nutella to the eggs and whisk until completely smooth and homogenous.
Gently fold in the sifted all-purpose flour using a silicone spatula just until no dry streaks remain. Do not overmix.
Pour batter into the prepared pan and bake for 20-25 minutes, or until a toothpick inserted in the center comes out with moist, sticky crumbs.
Allow the brownies to cool completely in the pan on a wire rack before lifting out and slicing into 16 squares.
