11ouncesdark chocolate, 60 to 72% cacao, coarsely chopped
1cup2 sticks unsalted butter, cut into 1-inch pieces
1teaspooninstant espresso powder
1 1/2cupsgranulated sugar
1/2cupfirmly packed light brown sugar
5large eggs, at room temperature
2teaspoonspure vanilla extract
Instructions
Preheat the oven to 350 degrees F. Butter the sides and bottom of a 9-by-13-inch baking pan.
In a medium bowl, whisk together the flour, salt, and cocoa powder; set aside.
In a large bowl set over simmering water, stir together chocolate, butter, and instant espresso powder until completely melted and smooth. Keeping the bowl over the water, turn off the heat and add the sugars. Whisk until completely combined. Remove the bowl from the pan and cool to room temperature.
Once the chocolate mixture is cool, add 3 eggs and whisk until combined. Add the remaining two eggs and whisk until combined. Add the vanilla; stir until combined. Be sure not to overbeat the batter at this stage or your brownies will be cakey.
Sprinkle the flour mixture over the chocolate mixture. Using a spatula, fold the flour mixture into the chocolate until just combined. (a bit of the flour mixture should still be visible).
Pour the batter into the prepared pan and smooth the top. Bake, rotating the pan halfway through baking time, in the center of the oven for 27-30 minutes until a toothpick inserted into the center of the brownies comes out with a few moist crumbs clinging to it. Place the pan on a wire rack and let the brownies cool completely. Cut into squares and serve.