Preheat your oven to 350°F (175°C). Line an 8 × 8-inch baking pan with parchment paper or lightly grease it.
In a medium mixing bowl, combine the creamy peanut butter, packed light brown sugar, and egg. Stir until the mixture is smooth and everything is fully incorporated.
Spoon the thick batter into the prepared baking pan. Spread it evenly into the corners using a spatula and smooth the surface.
Place the pan in the preheated oven and bake for 20–25 minutes, or until the edges are lightly golden and the center looks set. Avoid overbaking to keep the blondies soft and chewy.
Remove the pan from the oven and allow the blondies to cool completely before cutting.
Cut into 9 squares and enjoy these delicious peanut butter treats!
