Easy Rainbow Arc Cupcakes

Planning a rainbow birthday party or baby shower?  These gorgeous rainbow cupcakes look stunning but are surprisingly easy to make.

Use cake mix or make your own plain cakes in advance then whip up these amazing rainbow arc cakes to delight your guests. They're perfect for St Patrick's Day too!

These gorgeous little cakes look really impressive, but they're not as hard as they look!  Make up a dozen cupcakes first.  You can either use a cake mix box or your own recipe.  We used our fairy cakes recipe to make the cakes, simply double the quantity if you want deeper cupcakes.

These rainbow cakes are topped with a magical blue sky, puffy white clouds and a beautiful rainbow on top.

We used these unicorn tail licorice candy ropes or you could use these rainbow pencils in the UK.

Perfect for making with kids, or even as an activity at a birthday party.  These cupcakes would also make a lovely gift for friends or family, or give them away at the end as party favours.  Simply pop into a cupcake box or cellophane bag and tie with a ribbon.

Rainbow Cupcakes Recipe


12 pre-made cupcakes
Blue frosting or make your own
Mini Marshmallows
12 Rainbow ropes or pencils - buy in the US / buy in the UK

To make your own frosting:

175g / 6oz butter, softened
350g / 12oz icing sugar
Blue food colouring - buy in the US / buy in the UK


1. Make the frosting by beating the butter and icing sugar together until well blended.  Then add a drop or a two of food colouring at a time until you have the right colour.

2. Place frosting in a piping bag or large baggie and snip the corner.  Frost the cupcakes by swirling the icing around in a swirl.  Try to keep it quite flat rather than peaked.

3. Cut about a 1/3 off the licorice ropes and set those aside.  (Snacks later?)

4. Insert the longer pieces into the middle of the cupcakes.  Make sure to stay towards the middle and not get to close to the edge.

5. Place three marshmallows on each side to represent the clouds.

6. Serve and Enjoy!!

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