Line a baking sheet with parchment paper.

Drop 24 tablespoonfuls of Nutella onto the baking sheet, ensuring they don't touch.

Freeze the Nutella for about an hour, until solid.

In a medium bowl, whisk together the flour, corn flour, cocoa powder, baking soda, and salt.

In a large bowl, cream together the butter, sugar, and brown sugar until light and fluffy (about 2 minutes).

Beat in the eggs and vanilla extract until combined.

Gradually add the flour mixture to the butter mixture, mixing until just combined.

Stir in the chocolate chips, reserving some for topping.

Divide the dough into 24 portions.

Roll each portion into a ball, then flatten it slightly.

Place a frozen Nutella ball in the center of each dough ball.

Stretch the cookie dough to completely cover the Nutella ball.

Place the cookies on a baking sheet about 2 inches apart.

Sprinkle with the reserved chocolate chips.

Freeze the cookies for an hour.

Preheat the oven to 175 degrees Celsius (350 degrees Fahrenheit).

Bake the cookies straight from the freezer for 12-15 minutes, or until the edges are slightly crispy and the center is still soft.

Let the cookies rest for 10 minutes before serving.