Preheat your oven to 350°F (175°C) and grease an 8-inch round cake pan. Set it aside.

In a large bowl, whisk together the flour, cocoa powder, coconut sugar, baking powder, baking soda, and salt until evenly combined.

In a separate bowl, combine the almond milk, vegetable oil, and vanilla extract. Add the wet ingredients to the dry ingredients and mix until just combined.

Pour the batter into the prepared cake pan and spread it evenly. Bake for 25-30 minutes, or until a toothpick inserted into the center comes out clean. Let it cool completely in the pan.

While the cake cools, prepare the mousse. Melt the dark chocolate in a microwave-safe bowl or using a double boiler. Stir the chocolate until smooth and let it cool slightly.

In a mixing bowl, beat the aquafaba until it forms stiff peaks. This should take about 5-7 minutes.

In a separate blender, combine the melted chocolate, silken tofu, and maple syrup (if using). Blend until smooth and creamy.

Gently fold the whipped aquafaba into the chocolate mixture until thoroughly combined. You want to keep it airy, so mix gently.

Once the cake is cool, remove it from the pan. Spread a generous layer of the mousse on top of the cake.

Chill the cake in the refrigerator for at least 2 hours to set before serving.