In a medium bowl whisk together flour, cornstarch, baking soda, salt, cayenne pepper, and spices
Combine sugar and brown sugar in a small bowl. You'll roll the cookie dough in this mixture.
In the bowl of a stand mixer with the paddle attachment on medium speed, cream together butter, brown sugar, and sugar for 3-4 minutes
Add eggs, one at a time, mixing well after each one, using a spatula to scrape down the sides of the bowl, then add molasses
Stir in the dry ingredients until just combined (don't overmix)
Fold in the chocolate chunks
Refrigerate dough for one hour - this will make your cookies thicker and avoid spreading while baking
Roll dough into small cookie dough balls (about 2 tbsp) and roll through the sugar mixture, coating all sides, and place on a cookie sheet lined with a silicone mat or parchment paper
Bake at 400 degrees for 8-10 minutes or until golden brown on the top. Remove cookies when they turn light brown, but feel a bit underdone in the center, then cool on a wire rack for 15 minutes.