Preheat your oven to 350°F (175°C).

Prepare an 8x8-inch baking pan by greasing it or lining it with parchment paper.

In a large bowl, combine melted butter, brown sugar, and granulated sugar until smooth. Add eggs and vanilla extract, whisking until fully incorporated.

In a medium bowl, whisk together gluten-free flour, baking powder, and salt.

Gradually add the dry ingredients to the wet mixture, stirring gently until just combined.

Fold in chocolate chips and any additional mix-ins if desired.

Pour the batter into the prepared baking dish and spread it evenly.

Bake for 25-30 minutes 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 10 minutes, then transfer to a wire rack to cool completely before cutting into squares.