Preheat the oven to 350°F (175°C). Line an 8x8-inch baking pan with foil and spray the foil with nonstick cooking spray.
Prepare the brownie batter according to the pouch directions (or your recipe) for an 8x8-inch pan.
Spread the brownie batter evenly into the prepared pan. Sprinkle the semi-sweet chocolate chips and chopped pecans evenly over the top.
In a clean bowl, beat the 2 egg whites with an electric mixer or whisk until stiff peaks form.
Gently fold the brown sugar into the beaten egg whites until combined, then spread this meringue mixture evenly over the brownie layer.
Bake for about 35 minutes, or until the top is golden brown; if it browns too quickly, tent with parchment paper. Remove from oven and let cool completely before cutting.
Carefully peel away the foil before cutting. Spray your knife with cooking spray before slicing and re-spray after each cut to prevent sticking.