In the bowl of a food processor, combine dry ingredients by giving them 5 good pulses.

Distribute butter over the top, and pulse about 10 times, or until butter is cut in and the mixture resembles coarse meal.

With processor running, add buttermilk and process until dough comes together.

On a lightly-floured work surface, divide dough into two pieces, shape into rectangles about 1-inch thick. Wrap in plastic and refrigerate at least 30 minutes or up to one day.

Preheat oven to 375°F. Line two baking sheets with parchment or silicone baking sheets.

Place dough between two pieces of plastic wrap and roll to a thickness of 1/8-inch.

Cut into 1 1/2 inch diamonds and transfer to prepared sheets.

Bake about 15 minutes, or until dry and lightly browned around the edges.

Cool completely, then store in an airtight container.