Pre-heat oven to 350 F (177 C).
In a medium-large bowl, mush tofu with a spatula until smooth (you can also use a blender to get it extra smooth, but not necessary).
Once tofu is smooth, add in melted butter, sugar, vanilla and soy milk. Whisk together until well mixed.
In a separate bowl, whisk together dry ingredients - soy flour, cocoa powder, salt, baking soda and baking powder.
Slowly add the dry ingredients into your wet tofu mixture. Mix until well combined. This is an arm workout. Feel free to use a hand mixer or stand mixer to make it easier.
If baking dish is not non-stick, you may want to spray some oil onto the bottom and sides or line with parchment paper
Pour brownie batter into baking dish.
Cook for 30 - 35 minutes. Toothpick shouldn't come out completely clean because these will need to rest for at least 2 hours before serving. If you don't like gooey, fudgy brownies, you could cook these a little longer.