Note: Prep time does not include chilling time.
In a stand mixer with the paddle attachment cream butter until light and fluffy, 1-2 minutes.
Add in both sugars and cream for an additional 1-2 minutes or until combined.
Add in the egg and vanilla until combined and scrape down the sides of the bowl.
In a large bowl combine flour, cornstarch, baking soda and salt.
In two additions add the dry ingredients.
Fold in chocolate chips and chocolate chunks by hand.
Refrigerate dough for at least and hour or overnight.
When you are ready to bake preheat the oven to 350 degrees. Remove cookie dough from the refrigerator.
Scoop 1 heaping tablespoon of cookie dough and flatten dough into a thin bowl shape. Add ½ teaspoon of dulce de leche to the center of dough. Wrap dough around dulce de leche, being sure to fully enclose.
Place on a baking sheet lined with a silicone baking mat or parchment paper.
Bake for 10 - 11 minutes or until the cookies are golden brown. (I take mine out a little earlier and let them continue to cook on the pan)
Allow the cookies to cool for 5 minutes on the baking sheet then transfer to a wire rack to cool completely.