- 1/2 cup (1 stick) unsalted butter, plus more for pan
- 1 cup all-purpose flour, (spooned and leveled)
- 1/4 teaspoon baking powder
- 1/8 teaspoon salt
- 2 ounces unsweetened chocolate, coarsely chopped
- 1 ounce semisweet chocolate, coarsely chopped
- 1 cup packed dark-brown sugar
- 1/4 cup granulated sugar
- 2 large eggs
- 1 teaspoon pure vanilla extract
- 1 cup pecans, coarsely chopped
- Preheat oven to 350 degrees. Butter an 8-inch-square baking pan. Line bottom with parchment paper, leaving an overhang on two sides. Butter paper; set pan aside. In a medium bowl, whisk together flour, baking powder, and salt; set aside.
- Place butter and chocolates in a large heatproof bowl set over (not in) a saucepan of simmering water. Heat until smooth, 2 to 3 minutes, stirring occasionally. Remove from heat, and stir in sugars, eggs, vanilla, flour mixture, and half of pecans. Transfer batter to prepared pan; smooth top. Sprinkle with remaining pecans.
- Bake until a toothpick inserted in center comes out clean, 30 to 35 minutes. Set pan on a wire rack; let cool completely. Using paper overhang, lift brownie onto a cutting board; cut into 16 squares.
If you like, cut the brownies into shapes with cookie cutters; save the scraps to crumble over ice cream, or freeze and use them later.