Brownies

Preheat oven to 350 ° F
Line a 13” x 9” baking pan with buttered aluminum foil, allowing the foil to overhang the 2 ends of the pan by 2 inches
Position a rack in the center of the oven
In a large, heavy saucepan over very low heat, melt, stirring constantly until the mixture is smooth:
    12 or more Tablespoons cocoa powder (3/4 cup)
    12 Tablespoons butter (1 ½ sticks)
Set aside to cool completely. Stir in:
    2 cups sugar
    2 teaspoons vanilla
Stir in until well combined:
    1 cup all purpose flour
Stir in until well combined:
    4 large eggs
Stir in just until combined:
    1 cup chopped walnuts or pecans (optional)
    chocolate chips or other flavorings if desired
Scrape the batter into the pan and spread to the edges. Bake until the center is almost firm when lightly pressed and a toothpick inserted in the center comes clean, but still moist on the bottom, 23 to 28 minutes. Remove the pan to a rack and let stand until completely cool. Using the overhanging foil as handles, lift the brownie to a cutting board. Carefully peel off the foil. Cut into bars.

Note: 4 squares of chocolate may be used in lieu of the cocoa powder, but also reduce the butter by 4 Tablespoons (1/4 cup) when doing so (1 square of chocolate = 3 Tablespoons coccoa powder + 1 Tablespoon butter).