Preheat the oven to 180C/350F. Line an 8 x 8-inch square pan with parchment paper and set aside.
In a large mixing bowl, combine all ingredients and mix until fully combined. Pour batter into the lined pan and use a spatula to spread out.
Bake for 25-27 minutes, or until the tops are crispy and a toothpick comes out 'just' clean.
Remove from the oven and allow to cool in the pan. Once cooled, slice up.
* Traditional Nutella or sugar free Nutella (Nutilight)** For Nutella brownies without eggs, use aquafaba, flax eggs, or an egg replacement. TO STORE: Leftovers can keep at room temperature, in a sealable container. They will keep well for up to 5 days. Store them in the refrigerator to keep them for up to 2 weeks.TO FREEZE: Store them in a ziplock bag or container, and they’ll keep for at least 6 months.