PISTACHIO BISCOTTI THINS

Steps:

• Preheat oven to 350°F. and line bottom and sides of a 9 1/4 x 5 1/2 x 2 3/4-inch metal loaf pan with parchment paper.
• In a large bowl with an electric mixer beat whites with a pinch salt until they just hold stiff peaks. Gradually beat in sugar and beat until meringue holds stiff, glossy peaks. Sift flour over meringue and fold in with nuts and vanilla gently but thoroughly. Spoon meringue mixture into loaf pan, smoothing top, and bake in middle of oven until golden, 25 to 30 minutes. Cool loaf in pan on a rack 15 minutes and turn out onto rack to cool completely.
• Reduce temperature to 300°F.
• Peel off parchment and with a serrated knife cut loaf crosswise into 1/8-inch-thick slices. Arrange slices about 1/2 inch apart on 2 baking sheets and bake in upper and lower thirds of oven, switching position of sheets halfway through baking, about 20 minutes total, or until pale golden and crisp. Cool cookies on sheets on racks. Cookies keep in an airtight container at cool room temperature 1 week.