(©2005 Cook’s Illustrated)
1 cup pecans
1 1/2 cups flour
1 teaspoon baking powder
1/2 teaspoon salt
12 tablespoons (1 1/2 sticks) unsalted butter, melted and cooled
1 1/2 cups packed brown sugar
2 eggs, lightly beaten
4 teaspoons vanilla extract
1 cup white chocolate chips (I used half dark and half white = delicious)
Adjust oven rack to middle position; heat oven to 350°. Spread nuts on a rimmed baking sheet and bake until deep golden brown, 10-15 minutes. Transfer nuts to cutting board to cool; chop coarsely and set aside.
While nuts toast, cut foil to fit 9 by 13-inch pan; allow excess to overhang pan edges. Spray foil-lined pan with nonstick spray.
Whisk flour, baking powder, and salt together in medium bowl; set aside.
Whisk melted butter and brown sugar together in large bowl until combined. Add eggs and vanilla and mix well. Using a rubber spatula, fold dry ingredients into egg mixture until just combined; do not overmix. Fold in chocolate and nuts and turn batter into prepared pan, smoothing top with rubber spatula.
Bake until top is shiny, cracked, and light golden brown, 22-25 minutes; do not overbake. Cool on wire rack to room temperature. Remove bars from pan by lifting foil overhang and transfer to cutting board. Cut into 2-inch squares and serve.