Use a basic vanilla sponge cake for the cupcakes and allow to cool before starting.
You'll need a large ceramic flower pot (the top should measure 14")
A polystyrene ball (If you are doing this in a smaller pot just get a poly ball a couple of inches smaller than the diameter of the top of our pot)
Some small bits of polystyrene or something similar to build up from the bottom of the pot inside so your ball sits just proud of the top of the pot (e.g. just over half of the ball is protruding so you can stick your cakes to this)
Royal icing to stick everything on and together with
A large plastic piping bag full of a leaf green buttercream and large leaf nozzle (or just snip a 'V' shape in the end of the piping bag which will do to give you a leaf shape when you pipe if you don't have a nozzle)
Plenty of cupcakes piped in floral roses with buttercream in different shades of colours. Or just any colour cupcakes you wish. (Approximately 60)
To begin with, stick you polystyrene ball into the pot. Use some stiff royal icing in the bottom of the pot, and using broken pieces of polystyrene, build up , sticking with royal icing, until your ball can be stuck onto the poly pieces, so that the ball is sitting nicely in the pot, just over half way. The ball should be seen so you get a nice large floral cake display.
Begin attaching the cakes to the ball. start from the bottom of the display so that the cake cases can rest against the pot edge for support. Take a small palette knife and smear a dab of royal icing onto the bottom of the cake case, poke a cocktail stick into the bit of the polystyrene ball where you want to stick your first cake to leaving about an inch of cocktail stick pointing out from the polystyrene (this just helps to keep the cakes nicely in place).
Impale your first cupcake and push gently to the poly ball so the royal icing can hold.
Continue along the edge of the pot, leaving a small gap in between each cake, until you meet the starting point.
For the next row, do the same, add your cocktail sticks and push on the cupcakes, they will be able to rest on the row below, place them in between the middle of the bottom two beneath rather than sitting directly on the one below, so they look more fluid.
Continue all around the ball until you get to the top. You'll find you can sit a few in the top, just place them how you like and any gaps you can fill with 'buttercream leaves'.
Fill all of the gaps by piping the buttercream leaves in and around all of your cake flowers, just be random with it, and there you have it: a gorgeous, edible flowery cupcake bouquet centerpiece to wow your guests!
For the icing:
Place your icing sugar and egg white into the metal bowl of your mixer (I use a Kitchenaid) and your egg white. set the bowl into a pan of just simmering water to heat the mix whilst constantly beating with a whisk to dissolve the sugar. Tip: test the feel of this between your fingers, if it feels grainy it's not ready).
It will take a few minutes of beating with the whisk until you have a velvety smooth sugar and egg mix. It will feel slippery between your fingers and ward once it's ready.
Allow to cool
Pop the whisk attachment onto your machine (of course this can be done by hand but it will take a long time and lots of elbow grease) and whist the mix until very stiff and pure white. You want it to hold its shape. this will take a few minutes on high.
Now cut your room temp butter into cubes and add in small additions beating on slow to your egg white meringue mix. Once all the butter is incorporated, pour in the extract and scraped seeds from your vanilla pod.
Now turn up to high again and whip until the mixture transforms from a runny oily mix to a fluffy buttercream before your eyes.
Recipe courtesy of: Juliet Sear, owner of Fancy Nancy.