Preheat oven to 325F. Line baking sheet with parchment paper.
In a large bowl, combine oats, flour, baking powder, baking soda and salt. Set aside.
In a small skillet over medium heat, melt the butter until golden brown and has a nutty scent. Let it cool slightly, then add to the bowl of a standing mixer with the sugars. Blend until smooth. Mix in the eggs and vanilla. Add dry ingredients and stir just until combined. Gently stir in the hazelnuts and chocolate chips.
Drop rounded table spoon of dough onto prepared baking sheet for each cookie, with about 1″ spacing. Bake until golden brown, about 15 minutes. Let cool on baking sheet for about 5 minutes, then transfer to wire cooling rack.