Step 1

Preheat oven to 410 degrees.

Step 2

In large bowl, cream together cold butter and sugars until light and fluffy, about 4 minutes. Add eggs one at a time, mixing well after each addition.

Step 3

Add cocoa, cake flour, all-purpose flour, cornstarch, baking soda, and salt and stir until combined. Stir in semisweet chocolate chips.

Step 4

Chill dough for 15 minutes.

Step 5

Separate dough into large balls and place on lightly colored cookie sheet. Lightly press on top of dough to smooth out. If you have a scale, you can make them anywhere from 4.5 ounces - 6 ounces. You will fit 4-6 cookies on one large cookie sheet. The dough makes 8-12 extra large cookies.

Step 6

Bake for 9-11 minutes or until golden brown on the top. Let them rest for at least 10-15 minutes to set.