Move an oven rack to the middle position and heat the oven to 350°F. Prepare an 8x8" baking pan by lining it with parchment paper. Set aside.
Blend 10 ounces silken tofu, 1⅓ cups granulated sugar, ½ cup canola oil, 2 teaspoons instant coffee granules, and 2 teaspoons vanilla together until smooth using a blender or immersion blender. Set aside.
Whisk together 2 cups all-purpose flour, ½ cup cocoa powder, 1 teaspoon salt, and ½ teaspoon baking powder in a large bowl. Pour in the tofu mixture and stir together with a spatula. Fold in 3½ ounces chopped dark chocolate or chocolate chips. Note that the batter will be thick.
Spread the batter into the prepared baking pan and smooth the top of the batter with the spatula. Sprinkle a few additional chocolate chips over the top of the batter, if desired.
Bake until the edges of the brownies are set, but the center is still quite soft, about 30-35 minutes. Allow the brownies to cool to room temperature (at least 30 minutes) on a wire rack before cutting. Cut into squares and serve.