Preheat oven to 350°F (180°C). Lightly grease or line with parchment paper an 8-inch square pan.
Whisk together GF all-purpose flour, cocoa powder, sugar, baking powder, and a pinch of salt.
Add oil, vanilla extract, melted chocolate, and vegetable milk. Mix until well incorporated. You can add in this step dried fruits, chocolate chips, and so on.
Pour the mixture into the prepared pan and bake for 25 to 30 minutes.
Let cool before removing.
Notes
Store the brownies in an air-tight container at room temperature for 3 days or in the refrigerator for 5 days up to a week.