Whisk cocoa powder with hot melted butter before adding other ingredients to deepen chocolate flavor and eliminate any raw, bitter notes for a more complex taste.

Fold in flour gently just until combined to avoid developing gluten, which creates a cake-like texture instead of the desired fudgy, dense crumb.

Drop peanut butter dollops on the batter, then drag a skewer or knife through in one direction only for elegant, visible swirls that don't over-incorporate into the chocolate.

Remove brownies when a toothpick inserted in the center still has moist crumbs clinging to it—they'll continue cooking as they cool for that signature fudgy texture.

Sprinkle sea salt on the brownies immediately after removing from the oven to highlight the chocolate richness and create a sophisticated sweet-salty contrast with the peanut butter.