**Prepare the pan** Preheat your oven to 350°F (175°C). Line an 8x8-inch baking pan with parchment paper or lightly grease it.

**Make the brownie batter** In a mixing bowl, whisk together melted butter, granulated sugar, and brown sugar until combined. Stir in the eggs and vanilla. In a separate bowl, whisk flour, cocoa powder, and salt. Add the dry mixture to the wet ingredients, stirring just until combined.

**Bake** Pour the batter into the prepared pan, smoothing the top. Bake for 20–25 minutes, or until a toothpick inserted near the center comes out with a few moist crumbs. Avoid overbaking to keep brownies fudgy. Let them cool completely in the pan.

**Cut into petit fours** Once cooled, lift brownies out using parchment edges. Using a sharp knife, trim any rough edges if desired. Cut into small 1-inch squares. Place the squares on a wire rack set over a baking sheet.

**Prepare the glaze or ganache** In a microwave-safe bowl or small saucepan, warm the heavy cream until hot but not boiling. Add the chocolate chips (and optional corn syrup), letting them sit for 1 minute. Stir until smooth and glossy. If needed, thin the ganache with a bit more warm cream.

**Glaze the brownies** Pour or spoon the ganache over each brownie square, letting excess drip onto the baking sheet. Use an offset spatula to smooth the tops and sides if needed.

**Decorate and set** Add sprinkles, chopped nuts, or a white chocolate drizzle if desired. Allow the glaze to set at room temperature or in the refrigerator before serving.