Preheat the oven to 350-degrees. Spray a 9" x 13" baking pan with a cooking spray.
Combine the butter and brown sugar in a saucepan Cook over medium heat until the brown sugar has melted into the butter, stirring frequently. Remove the pan from the heat and allow to cool for about 10 minutes.
Add the eggs, one at a time, stirring well after adding each.
Ina separate bowl, whisk together the flour, the baking powder, and kosher salt.
Toss the flour mixture into butter, brown sugar, and eggs and stir until the well blended.
Stir in the vanilla extract.
Add the chocolate chips and the toasted pecans, stirring to blend evenly into the batter.
Scoop the batter into a 9” x 13” baking pan that has been sprayed with a cooking spray, spreading the batter as evenly as possible.
Bake in a 350-degree oven for 30 minutes and lightly golden on top. The brownies will firm up as they cool.