Congo Brownies

Directions

1. 1
   Before baking:
2. 2
   Center a rack in the oven and preheat the oven to 350 degrees F. Lightly butter a 13 by 9 by 2-inch pan (quarter sheet pan), then flour it, tapping out the excess flour.
3. 3
   To make the Congo Layer:
4. 4
   Sift together the flour, baking powder, and salt onto a sheet of waxed paper; set aside.
5. 5
   In a large bowl, stir together the butter, brown sugar, egg, egg white, and vanilla just until blended.
6. 6
   Stir in the flour mixture just until the batter is smooth.
7. 7
   Scoop the thick, sticky batter onto 8 or 9 different areas on the bottom of the prepared pan.
8. 8
   With an offset spatula, spread the batter to cover the pan as evenly as possible.
9. 9
   Sprinkle the walnuts evenly on top and gently press them into the batter.
10. 10
    Partially bake the layer until it is no longer shiny on top and is beginning to come away from the sides of the pan, about 20 minutes.
11. 11
    Transfer the pan to a wire rack to cool while you prepare the Brownie Layer.
12. 12
    To make the Brownie Layer:
13. 13
    Sift together the flour, cocoa powder, baking powder, and salt onto a sheet of waxed paper; set aside.
14. 14
    In a small, heavy saucepan, melt the butter and chocolate over very low heat, stirring with a silicone spatula until smooth.
15. 15
    Or, combine in a medium microwave-safe bowl and melt in a microwave oven at 50 percent power (medium) for 30-second bursts, stirring after each burst, until melted, 1 to 1 1/2 minutes.
16. 16
    Transfer to a medium bowl and let cool for 5 minutes.
17. 17
    Stir the sugar into the chocolate mixture until incorporated.
18. 18
    Add the eggs, egg yolk, and vanilla and stir until well blended.
19. 19
    Stir in the flour mixture just until the batter is smooth.
20. 20
    Scoop the thick, sticky batter onto 8 or 9 different areas of the still-warm Congo Layer.
21. 21
    With the offset spatula, spread the batter as evenly as possible.
22. 22
    Bake the brownie until the top is no longer shiny; appears set; feels firm, rather than soft; and a round wooden toothpick inserted in the center comes out with moist chocolate crumbs attached, about 25 minutes.
23. 23
    Transfer the pan to a wire rack and let cool completely.
24. 24
    The top layer will set up as it cools.
25. 25
    To make the Chocolate Glaze:
26. 26
    Place the chocolate in a medium bowl.
27. 27
    In a small saucepan, bring the cream just to a boil over medium-low heat.
28. 28
    Pour the cream over the chocolate and let it stand for 30 seconds.
29. 29
    Whisk together until smooth and creamy.
30. 30
    Set the mixture aside at room temperature just until it cools a bit and begins to thicken slightly.
31. 31
    Fashion a small cone out of parchment paper and half fill it with the liquid glaze.
32. 32
    Snip a small opening at the end of the paper cone to allow a thin flow of glaze.
33. 33
    Exerting light pressure on the cone, and never easing the pressure or halting the motion, pipe thin lines of chocolate in a zigzag pattern over the cooled surface of the brownie.
34. 34
    Set aside at room temperature until the glaze is set, 1 to 1 1/2 hours.
35. 35
    To serve, cut the brownie lengthwise into seven 1 3/4-inchwide strips, and then cut crosswise into seven 1 1/4-inch-wide strips, to yield forty-nine 1 3/4 by 1 1/4-inch bars.
36. 36
    Or, cut lengthwise into 6 strips and crosswise into 4 strips to yield twenty-four 2-inch squares.