Melt butter in a microwave-safe bowl. Whisk in granulated sugar and brown sugar until well combined.
Add eggs one at a time, mixing well after each addition. Stir in vanilla extract.
In a separate bowl, whisk together flour, cocoa powder, salt, and baking powder.
Gradually add the dry ingredients to the wet ingredients, mixing until just combined. Be careful not to overmix.
Grease and flour a 9×13 inch baking pan.
Pour the brownie batter into the prepared pan and spread it evenly.
In a medium bowl, combine brown sugar, melted butter, corn syrup, vanilla extract, and salt. Stir until well combined.
Stir in the pecan halves. Make sure the pecans are evenly coated with the brown sugar mixture.
Pour the pecan pie topping evenly over the brownie batter. Try and let some of the brownie peak through the pecan mixture.
Bake in a preheated oven at 350°F (175°C) for 30-35 minutes, or until a toothpick inserted into the center comes out with moist crumbs.
Let the brownies cool completely in the pan before cutting.
Once cooled, cut the brownies into squares. Serve and enjoy!
