Cooking spray
2 boxes of brownie mix and the ingredients needed to make the brownies
1 cup sugar
1 ½ cups corn syrup
4 large eggs
¼ cup unsalted butter, melted
1 ½ teaspoons vanilla extract
2 cups chopped pecans
Preheat the oven to 350 degrees Fahrenheit. Spray a 9x13-inch pan with cooking spray.
Follow the instructions on the brownie mix for making the brownie batter, and pour the batter into the prepared baking pan. Bake for 30 minutes.
Meanwhile, make the topping. In a medium bowl, stir together the corn syrup, sugar, eggs, butter, and vanilla until thoroughly combined. Add the pecans and stir to incorporate.
When the brownies are finished baking, immediately pour the topping over them and use a rubber spatula to spread the topping into an even layer.
Return to the oven and bake for 30 to 40 minutes more, until the filling is mostly set. Remove from the oven and let cool to room temperature in the pan.