Preheat oven to 350°F. Line one or two cookie sheets with parchment or silpat mats.

In a large mixing bowl or bowl of a stand mixer fitted with the paddle attachment, cream together butter and salt for 2 minutes, until creamy.

Beat in sugar and vanilla. Cream well for 2-3 minutes, scraping down the sides and bottom of bowl once or twice if using a stand mixer.

In a separate bowl, mix together flours and cocoa. Add to butter mixture slowly until the dough begins to ball up.

Using floured hands OR a spatula - bring the dough together to form a cohesive dough (fold the dough over 2 - 3 times to help bring it together). Then flatten the dough into a disc shape.

Either roll the dough out carefully between two pieces of parchment and cut into circles, about 1/4 inch thick, or shape into a 1/2 inch thick rectangle and chill for 15 minutes, then slice into bars.

Dock with a fork if desired.

Chill shaped cookies in the fridge or freezer until firm.

Bake the cookies in the center of the oven, for about 15 - 20 minutes, or just until the bottom edges of the cookies are starting to color. Make sure to check on the cookies every few minutes.*

Remove from the oven and allow the cookies to cool. Do not try to move the cookies until they are cooled.

Repeat with the second sheet pan of shortbread cookies. Store the cooled cookies in an airtight container.

Chocolate Shortbread