Heat oven to 350°F (176˚C)
Line an 9 x 9 (23 x 23) baking pan with parchment paper, leaving the ends hanging off the edges for easy removal of the brownies, or lightly grease the pan.
In a large mixing bowl, whisk together the 1 ⅓ cups of flour, ¾ cup of cocoa powder, ½ teaspoon baking powder, and ¼ teaspoon salt.
In a small bowl, melt the 12 tablespoon vegan butter and add to the flour mixture with the 1 ⅓ cups of sugar, egg replacer that is the equivalent of 2 eggs (follow the instructions on the package), 2 teaspoon of vanilla extract, and 1 cup of chocolate chunks and stir until combined. The batter should be thick.
Spread the batter evenly into the prepared baking dish.
Bake for 20 to 25 minutes or until the edges begin to pull away from the pan.
Cool before slicing.