First prepare the chocolate cake recipe as per the instructions on that recipe post & bake into cupcake tins, but be sure to only use 3Tbs batter for each cupcake
The bake time will be about half the regular time for normal sized cupcakes (approx 12-15 minutes)
Cool them completely then refrigerate while you prepare the buttercream recipe
Follow the instruction on the buttercream recipe then fill the cold cupcakes with the cream by hollowing out a small center space~ reserve in the refrigerator while you make the marshmallow
For the marshmallow: In a medium sized sauce pot over medium to high heat combine the water, granulated sugar, corn syrup and agar stirring to dissolve the sugar
Once the solution comes to a boil stop stirring & increase the heat to highInsert an instant read thermometer and continue boiling to 240°F About 5 minutes before the temperature of the sugar syrup reaches 240°F start whipping the aquafaba liquid with the cream of tartar with the balloon whip attachment of a stand mixer *see notes for success above!
Whip to stiff, glossy peaks then start pouring in the sugar syrup very carefully & very slowly! See video visual for how to do this!
Continue whipping the marshmallow until all the hot syrup is incorporated then add the vanilla extract & then quickly transfer the marshmallow to a pastry bag & pipe the marshmallow into the un-greased sphere molds
Insert the filled (COLD) cupcakes into each marshmallow pushing it in so the marshmallow comes up around the sides & to the top edge of the cupcake
These will set very quickly at room temperature, no need to refrigerate
Once set you can easily unmold each one & plunge into coconut flakes to coat the entire outside.