Preheat oven to 350F/176C and lightly coat two round cake pans with oil (I used two 7-inch pans). Dust with cocoa powder, shake out the excess, and set aside.
Mix together almond milk and vinegar in a large mixing bowl, and let set for a few minutes. Add the neutral oil, coffee, vanilla extract, and applesauce. Beat until foamy.
Sift flour, sugar, cocoa powder, baking soda, baking powder, and salt slowly over wet ingredients while mixing with a hand-held or standing mixer. If you don’t have a sifter, simply mix dry ingredients in another bowl and add to the wet mixture while beating by hand. Beat until no large lumps remain. It should be smooth and pourable.
Divide batter evenly between cake pans. Bake for 25-30 minutes, or until a toothpick inserted into the centre comes out clean. Let cool completely before frosting.
For the frosting: Add 2 inches water to a medium sized pot and bring to a simmer. Place a large glass bowl on top making sure the bottom of the bowl is not touching the water. Add dark chocolate and oil to the bowl to melt, stirring occasionally with a wooden spoon.
In a food processor combine melted chocolate with silken tofu, maple syrup, cocoa powder, rum, vanilla, sea salt and coconut milk. Blend until completely smooth and combined. Refrigerate.
Once the cake is cooled, frost generously with chocolate mousse frosting, adding a thick layer between the two tiers.