To make the macarons you will need;
200g ground almonds
200g icing sugar
2 x 80g egg white (at room temperature)
200g caster sugar
yellow and orange food colours
some royal icing
duck template (included in this Instructable)
For the buttercream (to fill the macarons and decorate the cupcakes) you will need;
130g unsalted butter (at room temperature)
1 teaspoon vanilla or lemon extract
600g icing sugar
yellow, blue and green food colours
For the cupcakes you can use whichever recipe you want to.
Step 1: Make your macaron batter
Place the ground almonds and icing sugar in a food processor and pulse a few times until well combined.
Sieve this into a large mixing bowl, discarding any lumps that don't pass through the sieve easily.
Place the caster sugar and water in a large saucepan. Place over a high heat and do not stir.
Meanwhile place 80g of egg white in the bowl of a food mixer and (with the whisk attachment) along with just one small drop of lemon juice. Mix gently to soft peaks.
When the temperature of the sugar syrup reaches 105° increase the speed of the mixer.
When the sugar syrup reaches 115° remove from the heat and pour in a thin ribbon onto the beaten egg whites, continuing to beat white you pour. I find a low speed helpful while pouring so the syrup doesn't splatter up the bowl. Continue to beat it on a high speed for a further 10 minutes until it is cool.
Take the remaining 80g of egg whites and stir into the almond and sugar until it forms a smooth paste.
Using a flexible spatula mix about a third of the Italian meringue mix into the almond paste, then add the rest of the meringue.
At this stage I took out about 10% of the mix and placed it in a separate bowl. Place 10% of the remaining meringue into this bowl and the other 90% into the original mix. To do this weigh your mixing bowl and deduct the weight you took at the beginning. Now divide this figure by 10.
Without mixing yet, add orange food colouring into the small amount of mix (i.e. the 10% bowl). I use powder colours and found I needed at least half a teaspoon. Don't leave it too late to add enough food colour as you will end up overmixing.
For the large (90%) bowl add at least 1 teaspoon of yellow food colour.
Be very careful not to overmix here (otherwise your macarons will not rise much and won't have feet). You should get it to a consistency where it will just drop the spatula smoothly and without being too runny. There are lots of resources on the internet that can show you how to achieve the perfect consistency.