For MLK Day: Black and White Shortbread Cookies

I wanted to do a dessert to honor Dr. Martin Luther King, Jr., and decided to do some black and white shortbread cookies.  If you've never made shortbread, it's practically the easiest thing in the world.  Anyone can do it.  And you can dress it up or down.  I made half vanilla-half chocolate cookies, but you could also make all vanilla cookies and then dip them in melted chocolate, or frost half of them with ganache.  You could add a little lemon, orange, or lime zest, or some cinnamon or anise or almond flavoring.  This is how I did it:

Black-and-White Shortbread Cookies

Ingredients:
4 cups flour
2 cups butter (4 sticks), room temperature
1 cup powdered sugar (you can also use regular sugar for a slightly different texture)
2 tsp vanilla extract
1/2 cup semi-sweet chocolate chips, melted

In a mixer, cream butter and sugar until light and fluffy, about 3 minutes, scraping down sides occasionally.  Beat in vanilla extract, then stir in the flour until just incorporated.  Divide dough in half; place one half on a sheet of plastic wrap and flatten to a disk.  Cover in plastic wrap and refrigerate for at least an hour.  Add chocolate to the second half of dough, stirring until evenly incorporated.  Flatten to a disk, wrap in plastic wrap and refrigerate at least an hour.

Preheat oven to 350F.  Line two baking sheets with parchment paper or silpat mats.

On a lightly floured surface, roll out the vanilla dough into a 1/4" thick rectangle.  Using a knife or bench scraper, cut a strip of dough 1" wide.  Repeat with remaining dough.  Reflour surface and roll out the chocolate dough in the same manner.

Take a strip of chocolate dough and put it next to a strip of vanilla dough.  Push the edges together slightly with your finger, then lightly run over them with a rolling pin to seal the edges.  Using and knife or bench scraper cross-cut the strip into 1" x 2" rectangles (half black, half white).  Transfer cookies to a baking sheet (they won't rise or spread, so you don't have to leave much room between them).  Repeat with remaining strips of dough.  Refrigerate cookies for 15 minutes before baking to firm up the butter, so cookies will maintain shape when baked.

Bake for 8-10 minutes, or until lightly brown.  Let set up for 5 minutes on baking sheet, then transfer carefully to wire rack to cool completely.

Shortbread will keep in an airtight container for a week, or frozen for several months.

Makes about 45 cookies.