Prepare: A 5-x-9-inch loaf pan, lined on the bottom and sides with foil or plastic wrap

Put the flour, sugar, coconut, and salt in a large mixing bowl and whisk to blend.

Cut the butter into the flour mixture with a pastry blender or two knives until the butter is reduced to small pieces.

With the fingertips of both hands, lightly toss and rub the mixture together until the mixture resembles coarse meal.

Combine the vanilla and cold water in a small pitcher or cup.

Stir the flour and butter mixture with a fork while drizzling the water and vanilla into the bowl. Continue to toss and stir lightly with the fork or your fingers until all of the dry ingredients are slightly damp. The dough should remain crumbly and stick together only when pinched.

Food Processor method: Place flour, sugar, coconut and salt in food processor bowl. Pulse 2-3 times to combine.

Cut butter into 1/2 inch cubes and scatter on top of flour mixture. Pulse until mixture reveals coarse meal. Small lumps are okay.

Combine water and vanilla extract in small cup. Continue to pulse the flour mixture and drizzle water into processor bowl.

Pulse into mixture starts to clump. It should not come together completely but will still be crumbly. It will stay together if pinched.

If using a loaf pan, dump the mixture into the lined pan and spread it evenly. Press it very firmly, making a thin layer. Or dump the mixture onto a piece of foil on a baking sheet and distribute it evenly over an area about 4 by 9 or 10 inches. Press it firmly, squaring up the edges, to make an even compact layer about 1/2-3/4 inch thick. Fold the foil over the dough and wrap it tightly. Refrigerate for 2 hours or overnight.

Preheat the oven to 350°F. Position racks in the upper and lower thirds of the oven.

Unwrap the dough and transfer it to a cutting board. Use a long sharp knife to cut the dough crosswise into 1/4-inch (or thinner if possible) slices. Use the knife to transfer each slice to the lined or greased cookie sheets, placing the slices 1 inch apart. The slices will be fragile and require the support of the knife in transit; the results will be worth your careful effort.

Bake for 11 to 14 minutes (baking time will vary depending on thickness of cookie), until the cookies are golden with golden brown edges. Rotate the pans from top to bottom and from front to back halfway through the baking time to ensure even baking.

For lined pans, set the pans or just the liners on racks to cool; for unlined pans, use a metal spatula to transfer the cookies to racks. Cool the cookies completely before stacking or storing.

May be kept in an airtight container for several days.