MAKES 36 BARS
If you have trouble finding white chocolate chips, chop a bar of white chocolate into small chunks.
1½ |
cups (7½ ounces) unbleached all-purpose flour |
1 |
teaspoon baking powder |
½ |
teaspoon table salt |
1½ |
cups packed (10½ ounces) light brown sugar |
12 |
tablespoons (1½ sticks) unsalted butter, melted and cooled |
2 |
large eggs |
1½ |
teaspoons vanilla extract |
1 |
cup (4 ounces) pecans, toasted and chopped coarse |
½ |
cup (3 ounces) semisweet chocolate chips |
½ |
cup (3 ounces) white chocolate chips (see note) |
1. Adjust an oven rack to the middle position and heat the oven to 350 degrees. Line a 13 by 9-inch baking pan with 2 pieces of foil (click here to see the photos) and spray with vegetable oil spray.
2. Whisk the flour, baking powder, and salt together in a medium bowl; set aside.
3. Whisk the brown sugar and melted butter together in a medium bowl until combined. Add the eggs and vanilla and mix well. Using a rubber spatula, fold the dry ingredients into the egg mixture until just combined. Do not overmix. Fold in the nuts and semisweet and white chocolate chips and turn the batter into the prepared pan, smoothing the top with a rubber spatula.
4. Bake until the top is shiny and cracked and feels firm to the touch, 22 to 25 minutes. Transfer the pan to a wire rack and cool completely. Loosen the edges with a paring knife and lift the bars from the pan using the foil sling. Cut into 2 by 1½-inch bars.