Preheat your oven to 350°F (175°C). Line an 8×8 inch pan with parchment paper.
In a microwave-safe bowl, combine the measured butter and semi-sweet chocolate chips. Heat in 30-second intervals, stirring until smooth.
Add the granulated sweetener and eggs to the melted mixture. Stir well until thoroughly combined. Incorporate the vanilla extract for added depth.
In a separate bowl, whisk together the gluten-free all-purpose flour blend, cocoa powder, and salt. Ensure there are no lumps.
Gradually add the dry blend to the wet mixture. Mix until just combined. Do not overmix.
Pour the batter into your prepared pan. Spread it evenly with a spatula.
Bake for 25-30 minutes. A toothpick inserted should come out with moist crumbs.
Let the baked goods cool completely in the pan on a wire rack. Slice and serve once fully cooled.