Bake the Cake Layers:

1. In a large bowl, beat the butter and the sweetener. Beat on medium speed, scraping down the sides of the bowl as necessary, until the mixture is pale yellow, light and fluffy, 1 to 2 minutes.
2. Beat in the eggs one at a time until incorporated into a curdled-looking thin batter.  In a medium bowl, whisk together the almond flour, unsweetened cocoa powder, baking powder, and teaspoon salt.  With the mixer at medium speed, add the flour mixture a little at a time to the egg mixture until combined - add the vanilla extract.  Pour the batter into a 8 x 8-inch square baking pan that has been lined with parchment paper.
3. Bake, rotating once during cooking, until the top springs back when lightly touched and a toothpick inserted into the center comes out clean, about 30 minutes.  Let cool on a wire rack for 15 minutes. Slide a small knife around the edges to release and invert the cake and place it on a wire rack set over a baking sheet to cool completely.  Slice the cake in half and set it in the freezer until ready to use.

Bake the Brownies:

1. Whisk together the oil and the eggs and then add all the remaining ingredients and stir to incorporate.  Spread the mixture into a loaf pan that has been greased well or lined with parchment paper.  Bake at 350 degrees for about 10-12 minutes.  Allow to cool and dice into small cubes.  Set the brownies to the side or freeze until ready to use.

Prepare the Chocolate Mousse:

1. Bloom the chocolate by combining the hot water and the cocoa powder and set it aside to cool slightly for about 5 minutes. 
2. Melt the chocolate in the microwave (30-second interval, stir and repeat for 15-second intervals until the chocolate melts). 
3. In a clean bowl, whisk the heavy cream, sweetener, and salt at medium speed for about 1 minute (or until it just begins to thicken).  Increase the speed to high and whip until soft peaks form.  Whisk the bloomed cocoa powder with the melted chocolate.  Using a whisk, whisk 1/3 rd of the whipped cream mixture into the chocolate mixture to lighten the mixture.  Then, using a rubber spatula, fold in the remaining whipped cream until no white remains.  Place the mousse in the fridge.

Prepare the White Chocolate Mousse:

1. In a small bowl, sprinkle the gelatin over the water - let sit for 5 minutes.  While waiting,  place the white chocolate in a small bowl.  Heat 1/2 cup of heavy cream to simmer (either in a saucepan or in the microwave) and add in the gelatin mixture and stir until fully dissolved.  Pour the cream mixture over the white chocolate and whisk until the chocolate has melted and the mixture is smooth.
2. Cool to room temperature stirring occasionally (about 5-8 minutes)
3. In a clean bowl, whisk the remaining 1 cup of heavy cream at medium speed for 1 minute and then increase to high speed until soft peaks form.  Using a whisk, whisk 1/3 rd of the whipped cream mixture into the white chocolate mixture to lighten the mixture.  Using a rubber spatula, fold in the remaining whipped cream until no white remains
4. Place the mousse in the fridge.

Assemble the Tuxedo Cake:

1. Take a high-rimmed loaf pan (or line a pan with acetate or aluminum foil to form a collar above the top rim) and line it with a parchment paper sling (this will allow for easy removal of the cake)
2. Place one of the cake layers on the bottom of the pan.  Spread the chocolate mousse over the cake and sprinkle the brownies over the mousse.  Next, spread the white chocolate mousse over the brownies followed by the remaining cake layer
3. Place in the fridge to set (at LEAST 3 hours but preferably overnight)
4. When ready to serve, remove the acetate or aluminum foil collard and use the parchment sling to remove the cake from the loaf pan.  Slice and enjoy!