01 -
Set your oven to 350°F. Grease and flour a 12x18-inch baking sheet or line it with parchment paper.
02 -
Use a double boiler to melt the butter, 16 ounces of chocolate chips, and the dark chocolate. Set aside to cool slightly.
03 -
In a big bowl, stir together (don’t whisk) the eggs, coffee powder, vanilla, and sugar until combined.
04 -
Pour the slightly cooled chocolate mixture into the wet ingredients. Let it cool again at room temperature.
05 -
Sift the 1 1/8 cups of flour with the baking powder and salt in a separate bowl.
06 -
Combine the dry mix with the chocolate mixture. Toss the remaining 12 ounces of chocolate chips and the nuts with the 1/4 cup of flour before folding them into the batter.
07 -
Pour the batter into the prepared pan. Bake for 20 minutes, tap the pan on the rack, then bake for another 15 minutes or until a toothpick comes out clean.
08 -
Let the brownies cool completely, then chill them in the fridge. Slice into 20 rectangular pieces before serving.