Preheat your oven to 350°F (175°C) and grease a 9x9-inch baking pan or line it with parchment paper for easy removal.
In a large mixing bowl, combine the creamy peanut butter, brown sugar, granulated sugar, and softened butter. Use an electric mixer or a whisk to blend the mixture until smooth and creamy.
Beat in the eggs one at a time, followed by the vanilla extract, mixing well after each addition.
In another bowl, whisk together the flour, baking powder, and salt. Gradually add this dry mixture to the wet ingredients, stirring until just combined.
Fold in the semi-sweet chocolate chips, ensuring they are evenly distributed throughout the batter.
Pour the blondie batter into the prepared baking pan and smooth the top with a spatula.
Bake in the preheated oven for 20-25 minutes, or until the edges are golden brown and a toothpick inserted in the center comes out with a few moist crumbs.
Allow the blondies to cool in the pan for about 10-15 minutes before transferring to a wire rack to cool completely.
Once cooled, cut them into squares and enjoy!
Notes
For best results, let the blondies cool completely before cutting.