For the Vegan Chocolate Cake:
Preheat oven to 350°F. In a large bowl, sift together the garbanzo flour, potato starch, cocoa powder, arrowroot powder, baking powder, baking soda, xanthan gum, and salt. In a second bowl, whisk together the coconut oil, agave, apple sauce, vanilla extract, and coffee. Whisk together the dry and wet ingredients. Line 5 half-sheet pans with parchment paper. Coat with nonstick spray. Divide the batter between the 5 pans. Bake 7 to 10 minutes until set, and cool. Freeze.
For the Mousse:
Melt the chocolate in a double broiler. In a food processor blend the tofu, sugar, vanilla, and salt. Slowly add the chocolate to the tofu mixture while food processor is running. Blend for 2 minutes.
To Assemble and Serve:
Mix the coffee and simple syrup together and cool. Punch out rounds of the Vegan Chocolate Cake and soak in the syrup, then layer with Mousse. Do this so each cake has three layers of Vegan Chocolate Cake.