Blondies

Preheat oven to 350°. Lightly coat a 13x9x2” baking pan with unsalted butter, room temperature, then line with parchment paper, leaving generous overhang on 2 sides. Butter parchment.

Whisk 2 cups (250 g) all-purpose flour, 1 tsp. baking powder, ¾ tsp. Diamond Crystal or ½ tsp. Morton kosher salt, and ¼ tsp. baking soda in a medium bowl.

Melt 10 Tbsp. (1¼ sticks) unsalted butter in large saucepan over low heat. Remove saucepan from heat. Add 2 cups (packed; 426 g) light brown sugar and whisk to combine. Whisk in 2 large eggs and 2 tsp. vanilla extract. Gradually stir in dry ingredients (batter will be thick). Spread batter in prepared pan. Sprinkle with ¾ cup semisweet chocolate chips (about 4½ oz.) and ¾ cup chopped pecans (about 3 oz.).

Bake blondies until golden-brown and a tester inserted into center comes out with moist crumbs attached, about 25 minutes. Let cool in pan on a wire rack. Cut into squares and serve. Do ahead: Blondies can be prepared 1 day ahead. Cover and let stand at room temperature.