Preheat oven to 248 F / 120 C. Put a parchment paper on top of a baking sheet.
Whip aquafaba in a clean ceramic or glass bowl for about 10 minutes or until it is completely white and looks like whipped cream.
Start adding sugar about 1 tbsp at a time. Continue whipping until each table spoon is fully incorporated in the aquafaba whip.
When all sugar is whipped and the aquafaba is getting very stiff, take about 1 cup of the fluffy cream aside for later.
Start adding the cocoa powder about 1 tsp at a time. Make sure to whip it well before adding another tsp.
NOTE: adding the cocoa powder is optional as it can get a little tricky. Sometimes when making this (depending on the cocoa) the aquafaba starts losing its fluffiness, but you just need to keep on whipping until the aquafaba doesn't come out of the bowl when you flip it upside down.
Take the white aquafaba and put it inside a piping bag. Pipe decorations for the cake on top of the parchment paper.
With a clean spoon scoop the rest of the aquafaba (the chocolate aquafaba if you added the cocoa powder) and make two equal sized round cake shapes on the parchment paper.
Bake in the oven for 2 hours. Don't open the oven before 1,5 hours in the oven, but you can check how your meringue is doing after about 1,5 hours. I usually check at 1 h 45 min and sometimes the small piped decorations are ready at this point. I just take them out with my hands without taking the baking sheet out of the oven.
When the meringues are ready let them cool down.
Melt 1,5 oz of dark chocolate in a water bath.
Chop a handful of cherries.
Whip the the oat for whipping cream and add melted dark chocolate. Continue whipping until it's fluffy and chocolatey.
Assembling the cake: place one meringue cake layer on the serving plate, add whipped cream on top, cherry jam, chopped cherries. Place the other meringue cake layer on top, spread whipped cream on top, add cherries and the piped meringue decorations.
To finish the cake shave dark chocolate on top.
Enjoy this delicious cake right away!