Ingredients

  • 13 cup Dutch-processed cocoa powder
  • 1 12 teaspoons instant espresso
  • 12 cup plus 2 tbsp. boiling water
  • 2 ounces unsweetened chocolate, finely chopped
  • 4 tablespoons unsalted butter, melted
  • 12 cup plus 2 tbsp. vegetable oil
  • 2 large eggs
  • 2 large egg yolks
  • 2 teaspoons vanilla extract
  • 2 12 cups sugar
  • 1 34 cups unbleached all-purpose flour
  • 34 teaspoon table salt
  • 6 ounces bittersweet chocolate, cut into 1/2-inch pieces

Method

  • Adjust oven rack to lowest position and heat oven to 350 degrees.
  • Cut 18" length foil and fold lengthwise into 8" width.
  • Fit foil into length of 13 by 9" metal baking pan, pushing it into corners and up sides of pan; allow excess to overhang pan edges.
  • Cut 14" length foil and fit into width of pan in the same manner, perpendicular to the first sheet.
  • Spray with nonstick cooking spray.
  • Whisk cocoa, expresso powder and boiling water together in large bowl until smooth.
  • Add unsweetened chocolate and whisk until chocolate is melted.
  • Whisk in melted butter and oil (may appear curdled).
  • Add eggs, yolks, and vanilla, and continue to whisk until smooth and homogeneous.
  • Whisk in sugar until fully incorporated.
  • Add flour and salt and mix with rubber spatula until combined.
  • Fold in bittersweet pieces.
  • Scrape batter into prepared pan and bake until toothpick inserted halfway between edge and center comes out with just a few moist crumbs attached, 30-35 minutes.
  • Transfer pan to wire rack and cool 1 1/2 hours BEFORE cutting.
  • Using foil overhang, lift brownies from pan.
  • Return brownies to wire rack and let cool completely, about 1 hour.
  • Cut into 2" squares and serve.