1. Preheat your oven to 350°F (175°C) and line a 9×13-inch baking pan with parchment paper.

2. Melt butter in a saucepan, remove from heat, and stir in granulated sugar and 1/2 cup brown sugar until combined.

3. Let mixture cool slightly, then whisk in eggs and 1/2 teaspoon vanilla extract until smooth.

4. In a separate bowl, sift together flour, cocoa powder, and salt. Stir into the wet mixture just until combined.

5. Spread brownie batter evenly into the prepared pan and bake for 20–25 minutes until partially set.

6. While brownies bake, combine 1/2 cup brown sugar, corn syrup, and heavy cream in a saucepan. Simmer gently, then remove from heat.

7. Stir in pecans and 1/2 teaspoon vanilla extract into the topping mixture. Let thicken slightly.

8. Carefully pour the pecan topping over the baked brownie base and spread evenly.

9. Return pan to oven and bake another 20–25 minutes until topping is bubbly and golden.

10. Cool completely in the pan. For best slicing results, chill in the fridge for 1–2 hours before cutting into squares.