Preheat oven to 350 degrees and spray a 9x13 baking pan with bakers spray and set aside.

In a large mixing bowl, add butter and beat well. Add brown sugar and white sugar and mix well. Add eggs and vanilla and mix well. Add flour, baking soda, baking powder and salt and mix until combined. Add chocolate chips and hazelnuts and mix until combined.

Press 2/3 of dough on bottom of baking pan and gently press with your fingers until the dough is evenly spread in pan. Spread the Nutella over the dough but keep a half inch border all around and do not spread it to the edges. Take pieces of the remaining dough and drop over Nutella so it evenly covers the entire surface. There will be gaps, but that is ok.

Bake for 25-30 minutes or until the dough is lightly browned. Remove and allow to cool completely before cutting.