These dark, fudgy brownies were made famous by Amy's Bread in New York! Nothing beats sinking your teeth into one of these warm, crumbly brownies, fresh from the oven!
Preheat oven to 350°F (175°C). Grease a 9"x 13"x 2" baking pan. Line the bottom of the pan with parchment paper.
Melt the butter, half of the chocolate chips, and the unsweetened chocolate in a double boiler (or microwave). Set aside to cool to warm.
Whisk the sugar, eggs, and vanilla just until mixed. (Over-mixing will cause crumbly brownies.) Fold in the warm chocolate mixture.
Whisk the flour, baking powder, baking soda, and salt. Fold the flour mixture into the chocolate mixture until just combined. Stir in the remaining chocolate chips and nuts (if using), mixing just until combined.
Pour the batter into the prepared pan, spreading evenly. Bake 32-36 minutes. The edges will be slightly firm and the center will be soft when they are fully baked. Do not overbake. Cool completely in the pan on a wire rack.
Notes
These brownies may cut better if they are chilled first.