Put the flour, cheese, salt and cayenne in the bowl of your food processor and pulse briefly to combine.

Add the butter and pulse until the butter pieces are slightly larger than pea size, about 10 to 12 pulses depending on your machine.

Add the largest pieces of pistachio to the mix (leave the finer crumbs on the counter to garnish the dough) and pulse one or two times.

Drizzle the water evenly over the flour mixture.

Pulse until the dough begins to form moist crumbs that are just beginning to clump together, about 8 or 9 more pulses depending on your machine.

Empty the crumbs onto a counter-top (without flour) and gather into a pile. With the heel of your hand, push and gently smear the crumbs away from you until they start to come together in a cohesive dough.

Two or three ‘smears’ should do the trick. Using a bench scraper, gather the dough together and turn it about 45 degrees and give it one or two more smears.

Gather the dough together and shape the dough into a 7 1/4-inch long and 2 1/4 -inch wide rectangle using the bench scraper to make the sides nice and straight.

Press the fine pistachio crumbs left from processing into the top and/or bottom of the dough depending on how much you have.

Wrap tightly in plastic wrap and refrigerate until very firm, about 3 hours, or up to 2 days.

Position a rack in the center of the oven and heat the oven to 375°F. Line two large baking sheets with parchment.

Using a thin, sharp knife, cut the logs into 1/4-inch slices and arrange about 1 inch apart (without leavening you don't really have to worry about them spreading) on the prepared sheets.

Bake, one sheet at a time, until nutty brown around the edges, 16 to 18 minutes.

Serve slightly warm or room temperature.