Combine flour, cocoa, cornstarch, baking soda, and salt in a large bowl.
Whisk to mix. Set aside
Cream together in a large mixing bowl the butter, white, and light brown sugar using an electric
mixer until it becomes light in color and fluffy.
Add in the three eggs, pure vanilla, and corn syrup mixing until completely mixed.
Continue beating while adding in the flour mixture until a soft cookie dough begins to form.
With a large ice cream scooper, scoop dough into your hands and roll it into a ball
Place on the cookie sheet about 2 in apart from the other dough
Use your hands to flatten the dough into the same size circles.
Bake at 350 degrees for 15-17 minutes.