Preheat your oven to 350 degrees and line 2 cookie sheets with parchment paper.

Whisk together your flour, oats, baking powder, baking soda, and salt. Set aside.

Add your butter and both types of sugar to a large bowl and mix on medium speed until the butter is light and fluffy (about 3-5 minutes). Add the eggs and vanilla and continue to mix until they're thoroughly blended.

Gradually add in the flour mixture (make sure each addition has been mixed in before adding more). Then add the hazelnuts and chocolate chips and fold them in with a wooden spoon.

Measuring the dough with a tablespoon, drop the cookies onto the baking sheet 2" apart and bake for 15-18 minutes or until the edges have set. Cool the cookies for 5 minutes on the baking sheet, then transfer them to a wire rack to finish cooling.