Preheat oven to 400 degrees.
In mixer fitter with paddle attachment, add in the butter, sugar, salt and cayenne pepper. Mix on high for about 2 minutes, or until creamy.
With mixer on lowest setting, add in flour one cup at a time.
Add in eggs, one at a time.
Mix until just combined then turn off mixer and remove bowl.
Add in chocolate chunks and mix by hand until incorporated.
Grease 12 inch cast iron skillet and press cookie dough into pan until flat and even.
Bake for 28-33 minutes, or until edges are golden brown.
Can be served immediately, but be careful!