Add the eggs and vanilla extract. Mix until well combined.
Bake for 12-14 minutes or until the edges are golden brown.
Flatten each ball slightly using the back of a fork.
Fold in the ground hazelnuts with a spatula.
Gradually mix the dry ingredients into the wet mixture until just combined.
In a large bowl, cream together the butter, granulated sugar, and brown sugar until smooth.
In a separate bowl, whisk together the flour, baking powder, and salt.
Let the cookies cool on the baking sheet for 5 minutes before transferring them to a wire rack to cool completely.
Preheat the oven to 350°F (175°C). Line a baking sheet with parchment paper.
Roll tablespoon-sized scoops of dough into balls. Place them 2 inches apart on the baking sheet.
Enjoy these delightful hazelnut cookies with a cup of tea or coffee!