Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper.
In a large mixing bowl, cream together the softened butter, brown sugar, and granulated sugar until light and fluffy.
Beat in the egg and vanilla extract until fully incorporated.
In another bowl, whisk together the flour, baking soda, and salt. Gradually add this dry mixture to the wet ingredients, mixing until just combined.
Fold in the dark chocolate chips and chopped hazelnuts, ensuring they’re evenly distributed throughout the cookie dough.
Take about 2 tablespoons of cookie dough and flatten it in your palm. Place a teaspoon of chocolate hazelnut spread in the center and wrap the dough around it, rolling it into a ball.
Repeat this process with the remaining dough and hazelnut spread. Place the dough balls on the prepared baking sheet, leaving space for them to spread.
Gently press some chopped hazelnuts on top of each cookie for extra crunch and flavor.
Bake the cookies in the preheated oven for about 10-12 minutes, or until the edges are golden brown but the centers still look soft.
Allow the cookies to cool on the baking sheet for 5 minutes before transferring them to a wire rack to cool completely.
Notes
Serve warm with a glass of milk or coffee, and sprinkle a light dusting of powdered sugar on top for an elegant touch.