Ingredients
- 8 tablespoons (1 stick) unsalted butter, plus more for the pan
- 1¼ cups sugar
- ¾ cup unsweetened cocoa powder
- ¾ teaspoon vanilla extract
- ¼ teaspoon kosher salt
- 2 cold large eggs
- ½ cup all-purpose flour
- 1 cup plus 2 tablespoons finely chopped walnuts, pecans, and/or mini chocolate chips
How to Make It
- Set a rack in the middle of the oven and preheat it to 325°F. Very generously butter an 18- by 13-inch rimmed baking sheet (do not line it with parchment).
- Melt the 1 stick butter in a small heatproof bowl in the microwave or set over a pot of barely simmering water.
- In a medium bowl, whisk together the sugar, cocoa powder, vanilla, and salt. Pour the melted butter over the sugar mixture and stir until smooth. Add the eggs, one at a time, stirring vigorously with a wooden spoon or rubber spatula after each addition, until the batter is thick, shiny, and smooth. Stir in the flour until well incorporated, then beat vigorously for 30 to 40 strokes. Stir in the nuts and/or chocolate chips.
- Using a spatula, transfer the batter to the baking sheet and spread it into a thin, even layer, all the way to the edges and into the corners of the pan. (The batter will seem scant, but the brownies will rise to about ¼ inch thick).
- Bake until the brownies are firm to the touch and a tester inserted into the center comes out with moist crumbs (not runny batter) attached, 15 to 18 minutes. Transfer the baking sheet to a wire rack and let cool completely. Cut into 36 pieces and serve, or pack the brownies into an airtight container and keep at room temperature for 4 days or so, or in the freezer for up to 3 months.