I made these particular macarons to sit on top of my 21st birthday cake (and because I think no afternoon tea is complete without them!) Feel free to adapt the colours or flavours as you wish.
Ingredients (makes around 40 macarons, 20 paired)
Macaron shells
225g pure icing sugar
130g almond meal
115g egg whites
60g caster sugar
1g bicarb soda
A few drops of rose pink & violet food colouring
Vanilla bean filling
100g butter, softened
¼ cup milk
½ tblspn organic vanilla bean paste
4 cups icing sugar
Rose pink & violet food colouring
Method
Preheat oven to 150°C fan forced. Grease and line two large baking trays with baking paper.
Separately sift icing sugar and almond meal into medium bowls or over sheets of baking paper. Repeat process 3 times and re-weigh ingredients (I know this seems excessive but trust me, it’s worth it). You will need to top up the ingredients as you may have lost some in the sifting process. Sift icing sugar and almond meal into a bowl and repeat, ensure there are no lumps.
Whisk egg whites until doubled in size using electric beaters or an electric stand mixer. While still whisking, gradually add caster sugar and bicarb, whisking until mixture forms very stiff peaks.
Gently fold almond meal mixture into meringue using a spatula until incorporated.
Divide mixture into 2 bowls. Add food colouring (pink to one, purple to the other) one drop at time, stirring very gently with a spatula, until desired colour reached.
Spoon into a piping bag fitted with a 9mm round nozzle (approximately). Hold nozzle close to the baking tray and pipe 3cm diameter circles onto prepared trays – don’t make a circular motion àla soft serve. Tap the underside of the tray to allow macarons to settle and air bubbles to escape. If there is still a little peak on top, dip a teaspoon in water and use the back to smooth the surface. Repeat with other colour. 
Leave to rest for at least 20-30 minutes or until the macarons form a skin and the top is no longer shiny or sticky to the touch (this is VERY important as it will give your macaron its lovely ‘foot’).
Bake for 12 minutes. Remove trays from the oven and allow macarons to cool on the tray. They will still be soft at this stage but will firm up on cooling.
To make the buttercream, cream the butter for 1-2 mins. Add the milk, vanilla and half of the icing sugar and beat for at least 3 mins (until the mixture is light and fluffy).
Add the remaining icing sugar and beat for a further 3 mins or until of a spreadable consistency. Add extra milk if too dry or extra icing sugar if too wet.
Halve the mixture and add a drop of rose food colouring to one half and a drop of violet colouring to the other.
Pipe a generous amount of buttercream onto half the macarons and sandwich with a second macaron.
Recipe adapted from Callum Hann’s ginger macarons
Bakerholics Anonymous 
