Preheat oven to 350°F (175°C) and grease a 9-inch pie dish or oven-safe skillet.

In a large bowl, cream together the softened butter, brown sugar, and granulated sugar until light and fluffy.

Beat in the egg and vanilla extract until well combined.

In a separate bowl, whisk together flour, baking soda, and salt, then gradually mix into the wet ingredients.

Fold in the chocolate chips to complete the cookie dough.

Divide the dough in half and press one half into the bottom of the prepared pie dish.

Spread the Nutella evenly over the dough base, leaving a 1/2-inch border at the edges.

Flatten the remaining dough into small discs and place them over the Nutella, pressing the edges to seal.

Bake for 25 minutes or until the edges are golden brown and the center is set.

Cool for at least 15 minutes before serving to allow the Nutella center to stabilize.