Preheat the oven to 350 °F (175 °C) and line an 8"×8" (20cmx20cm) pan with parchment paper.
In a medium mixing bowl, stir together the flour, cocoa powder, and salt. Set aside.
125 grams (1 1/3 cups) oat flour, 3/4 cup (86 grams) Dutch-process cocoa powder, 1/4 teaspoon salt
In a large mixing bowl, stir together the melted coconut oil, sugar, and vanilla extract. Once combined, add the eggs one at a time, and stir just until combined.
3/4 cup (168 grams) refined coconut oil, 1 1/2 cups (300 grams) granulated sugar, 1 tablespoon vanilla extract, 3 large eggs
Add the dry mixture to the wet and stir just until almost no streaks of flour remain. Do not overmix! Fold in 3/4 cup (128 grams) chocolate chips.
3/4 cup (128 grams) semi-sweet chocolate chips
Pour the batter into the prepared pan and sprinkle the remaining 1/4 cup (43 grams) chocolate chips on top.
Bake for 16-20 minutes or until the brownies have formed a thin crust and appear set in the middle. A toothpick inserted into the center will come out wet. A toothpick inserted into the sides will come out with some moist crumbs on it, but not totally raw batter. The brownies will continue to bake as they sit in the pan and will firm up as they cool.
Place on a wire rack to cool completely, about 2 hours, and then refrigerate them about 2-3 hours to give them a fudgier texture.
Store leftover brownies in an airtight container in the fridge for up to 5 days. You can also freeze them in a freezer-safe bag or container for up to 3 months.