Instructions

• Preheat the oven to 350°F. Line an 8×8-inch baking pan with parchment paper and lightly spray the parchment and pan; set aside.
• Place the 1/3 cup melted butter and the 8 ounces chopped semi‑sweet baker’s chocolate in a microwave‑safe bowl. Microwave in 30‑second intervals, stirring well between intervals, until the chocolate and butter are fully melted and smooth.
• Let the chocolate mixture cool slightly (about 1–2 minutes) so it is warm but not hot.
• Whisk the ¾ cup granulated sugar, 1 teaspoon vanilla, and 1/4 teaspoon salt into the warm chocolate mixture until combined.
• Add the 2 beaten large eggs one at a time, whisking after each addition until just combined.
• Add the 3 tablespoons dark cocoa powder and 2 tablespoons cornstarch. Whisk or fold until the batter is smooth and no lumps remain.
• Pour the batter into the prepared pan and smooth the top with a spatula. Sprinkle the 1/4 cup chocolate chips or chocolate chunks evenly over the top.
• Bake for 25–30 minutes, until the center is just set—an inserted toothpick should come out with a few moist crumbs (do not overbake).
• Allow the brownies to cool completely in the pan on a wire rack before lifting out on the parchment and slicing.