Preheat your oven to 350°F and line an 8x8 inch baking dish with parchment paper, allowing the paper to overhang slightly on two sides for easy removal later. This setup ensures even heat distribution and makes removing your cooled brownies simple and clean.

In a heat-safe bowl, combine the butter and chocolate chips, then melt them together over low heat or using a double boiler, stirring occasionally until completely smooth. I find that melting them together creates a more cohesive chocolate base than melting them separately—the butter helps distribute the cocoa butter evenly for a silkier texture.

In a mixer, beat the room-temperature eggs and sugar together for 2 minutes on medium-high speed until the mixture becomes pale, fluffy, and roughly doubled in volume. This aeration is crucial—it creates tiny air pockets that give the brownies their tender, fudgy crumb rather than a dense, heavy texture.

Pour the melted chocolate mixture from Step 2 into the egg and sugar mixture from Step 3, folding gently with a spatula until just combined and no streaks of egg mixture remain. Be gentle here—you want to preserve those air bubbles you just created rather than deflate them with aggressive stirring.

Sift the cocoa powder into the batter, then add the cassava flour, vanilla, and a pinch of salt, folding everything together gently until just combined with no flour streaks visible. I always sift the cocoa powder to avoid clumps and ensure it distributes evenly throughout the batter for consistent chocolate flavor in every bite.

Pour the batter into the prepared pan from Step 1 and bake for 15 minutes until the edges are just set but the center still looks slightly underdone. Remove the pan and tap it firmly on the counter a few times—this helps release air bubbles and encourages the characteristic fudgy texture. Return to the oven for another 10-12 minutes until a toothpick inserted in the center comes out with just a few moist crumbs (not wet batter).

Remove the brownies from the oven and immediately sprinkle the sea salt garnish over the warm surface, allowing it to adhere slightly. Let the brownies cool completely in the pan (at least 2 hours or overnight is best), then use the parchment overhang to lift them out and cut into squares. The cooling time allows the structure to set properly, making clean cuts possible.