Line a small baking sheet with parchment paper. Using a spoon, drop the Nutella into small drops (about a teaspoon in size) on the parchment paper. This recipe will make about 20-22 cookies, so I suggest making about that many. Place in the freezer and freeze for about 1 hour.
In a large bowl, whisk together the flour, cocoa powder, baking soda, and salt. Set aside.
Using a handheld mixer or stand mixer fitted with the paddle attachment, beat the butter, brown sugar, and granulated sugar until light and fluffy. Add in the egg and vanilla, making sure to mix well after each ingredient.
Slowly add the dry ingredients to the wet ingredients and mix until just combined.
Add the chocolate chips and mix them into the batter.
Cover the cookie dough and refrigerate for at least 45 minutes (this will make the dough much easier to work with).
Preheat oven to 350°F degrees. Line two large baking sheets with parchment paper or a silipat mat.
Remove the dough from the refrigerator. Take two tablespoons of dough at a time and drop it on the prepared baking sheet.
Remove the Nutella from the freezer. Flatten each piece of dough, place one teaspoon of the Nutella in the center, then fold the dough back around it making sure the Nutella is completely closed inside.
Bake at 350°F for 10-12 minutes.
Remove from the oven and allow to cool on the baking sheet for 10 minutes, then transfer to a wire rack to finish cooling.
Storage instructions: Cookies may be stored in an airtight container at room temperature for up to five days.