Arrange the donuts into 3 piles of 4 donuts each.
Spread the chocolate mousse onto 1 donut and top with another donut. Spread the chocolate mousse onto that donut and place another on top. Repeat until the 4 donuts are joined together.
Repeat the process for the other 2 piles.
Pipe/spoon more Chocolate Mousse into the centre of the donut piles, filing the donut tunnel.
Smear a spoonful of mousse on the serving tray to act as the glue for the donut piles.
Place the donut 'piles' on a serving plate (refer to the step by step photos).
Completely cover the donuts with the cherry whipped cream, making sure no donut is visible.
If needed, make extra whipped cream to ensure that all the donuts are fully covered.
Use a piping bag to decorate the base of the cherry ripple cake with chocolate mousse (it also helps to hide any cream smears on the serving plate).
Place in the fridge for a minimum of 3 hours before serving.
Slice from the narrow end. Each slice will have a cross section of a '4 donut sandwhich'.