Pistachio Melbas

Description
This biscotti-like cookie is derived from the Eastern European/Jewish cookie Mandelbrot. Australians adopted it, and renamed it Mandel-Melba, due to its textural similarity with the Australian favorite Melba toast (named, of course, for the opera singer Dame Melba). We've used pistachios here, with lemon and orange zests to brighten the flavor. They're not super-sweet; they're more of a cookie to have with your tea or coffee. The key to this is to slice it super-thin so it crumbles in the mouth.
 * Contributed by Catsrecipes Y-Group

Ingredients

 * unsalted butter, softened
 * 1½ cups all-purpose flour, plus more for the pan
 * ¼ teaspoon fine salt
 * 1 cup sugar
 * finely grated zest of 2 lemons (about 1 tablespoon, packed)
 * finely grated zest of 1 orange (about 2 teaspoons, packed)
 * 4 large eggs
 * 1 cup whole raw peeled pistachios

Directions

 * 1) Position a rack in the center of the oven and preheat to 350°F.
 * 2) Brush a 9 by 5-inch loaf pan with butter and dust it with flour.
 * 3) Whisk the flour and salt together in a bowl.
 * 4) In another medium bowl, rub the citrus zests into the sugar with your fingers until the sugar is fragrant and takes on a bit of the fruit color.
 * 5) Beat the eggs into the sugar with a wooden spoon until blended.
 * 6) Stir in the flour mixture to make a smooth, sticky but pourable batter.
 * 7) Stir in the pistachios.
 * 8) Pour the batter into the prepared pan, and smooth the surface lightly with a spatula.
 * 9) Bake until the loaf is lightly browned and pulling away from the sides of the pan, about 40 to 45 minutes.
 * 10) A skewer inserted into the center should come out clean, and the loaf will look like a not so great pound cake.
 * 11) Let stand for 10 minutes, then remove from the pan and cool on a rack for 1 hour.
 * 12) Wrap the loaf in plastic and freeze until firm, about 30 minutes.
 * 13) Preheat the oven to 300°F.
 * 14) Slice the chilled loaf as thin as you can - 6 to 8 slices to the inch (it helps to mark the loaf lightly with a serrated knife every half-inch and use that as a guide).
 * 15) Lay the slices flat on 2 baking sheets and bake until brown, 10 to 15 minutes (take care - the cookies can go from pale to dark brown quickly).
 * 16) Let stand overnight or for at least 12 hours on a rack to cool and crisp up.
 * 17) Serve.
 * 18) Store in a well-sealed jar or other container.

Busy baker's tips
The loaf can be stored well-wrapped at room temperature for a week, or frozen for a month. The melbas are best stored in an airtight container, away from moist cookies and cakes. Freeze slices double-wrapped in plastic wrap for up to 1 month. Defrost in their wrappers.