Preheat oven to 350 degrees F. Line baking sheets with parchment or a Silpat mat and set aside.

In a large bowl combine flour, baking soda, cocoa powder and salt and whisk to combine.

Cream together butter and sugars in a large bowl until light in color.

Add in eggs, one at a time, beating well after each addition. Add in vanilla.

Add in flour mixture to egg mixture and mix just until combined.

Add in chocolate chips.

Refrigerate batter for 10 minutes.

Drop dough by tablespoonfuls onto prepared baking sheet.

Bake at 350 degrees F. for 7 to 10 minutes until set.

Allow to cool on cookie sheet for 2 - 3 minutes then remove to cooling rack to cool completely.