- 10 tablespoons (1 1/4 sticks) unsalted butter
- 1 cup sugar
- 3/4 cup unsweetened cocoa powder
- 1/4 teaspoon salt
- 1/2 teaspoon pure vanilla extract
- 2 cold large eggs
- 1/2 cup all-purpose flour
- 1/2 cup walnut or pecan pieces, chopped (optional)
Preheat the oven to 325°F. Line the bottom and sides of an 8-inch square pan with aluminum foil, leaving an overhang on both sides.
Combine the butter, sugar, cocoa, and salt in double boiler. Stir from time to time until the butter is melted and the mixture is smooth and hot. Remove from heat and let cool slightly.
Stir in the vanilla, and then add the eggs one at a time, stirring vigorously after each one. When the batter looks thick and well blended, stir in the flour, then beat vigorously for one minute with a wooden spoon or rubber spatula. Stir in the nuts, if using. Spread evenly in the prepared pan.
Bake until a toothpick stuck into the center emerges only slightly moist with batter, 20 to 25 minutes. Let cool completely, then lift out the foil and peel it away. Cut the brownies into 16 or 25 squares.