Rainbow Swirl Cupcakes by Juliet Sear

Method

1. Preheat the oven to 180ºC (350ºF/Gas 4). Grease 2 x 20 cm (8 in) round cake tins or a 12-hole cupcake tray.

2. Place the butter, sugar and vanilla or other flavourings into a mixing bowl and combine. If using an electric mixer, turn the speed to high (or if you’re using a wooden spoon, use plenty of elbow grease!) and beat until the mixture is very pale, soft and fluffy and the granules of sugar have disappeared.

   • 300g Butter (salted)
   • 300g Golden caster sugar (We like Billington's)
   • 2 tsp Vanilla bean paste (We like Nielsen Massey)

3. Add the beaten eggs, about one-quarter at a time, beating them in slowly each time.

   • 6 Eggs (Medium)

4. Add the flour gradually, one-quarter at a time, mixing gently on a slow speed, until it has mostly been incorporated. Then, add the baking powder. Fold with a metal spoon if doing this by hand. Take care not to mix or beat vigorously or your sponge can turn out a bit tough. Scrape the mixture into cupcake cases or lined tins as required.

   • 300g Self raising flour
   • 1 tsp Baking powder

5. For cupcakes, bake for around 12–15 minutes, checking every few minutes. For a larger cake, begin checking after 20 minutes. Remember, all ovens vary so if in doubt use an oven thermometer. The cakes should be a light golden brown, springy to the touch. A sharp knife or metal skewer should come out clean and free of mixture when inserted into the centre.

6. Leave to cool for a couple of minutes in the tins, then turn out onto a cooling rack. 

   Top Tip: Storage

   Storage

   Cupcakes: once these are iced they will last well for 2–3 days. If frozen, they’ll keep for 1 month. I use a corrugated cupcake box with little inserts to keep them in shape, then wrap cling film (plastic wrap) around the box. Allow to come to room temperature for 3–4 hours before using.

   Larger cakes: these can be double-wrapped in cling film and popped into a freezer bag with a bag tie for up to 1 month. Remove from the freezer the night before using.

7. If you have an electric stand mixer then use this with the beater or paddle attachment. Otherwise, use a hand-held mixer or a wooden spoon. Scrape the seeds from the vanilla pod, if using, or add the paste. In the mixer or bowl, cream the butter with the vanilla seeds and extract until very pale, creamy and smooth.

   • 2 tsp Vanilla bean paste (We like Nielsen Massey)
   • 250g Butter (unsalted)

8. Add about one-quarter of the icing sugar. To make sure the sugar doesn’t puff out in clouds and cover your kitchen, mix slowly at first. You can also place a damp tea towel over the bowl. Once the icing sugar is incorporated, beat at a high speed for about 1 minute until the mix is really creamy and pale. It will take you a few more minutes by hand.

   • 500g Icing sugar (We like Silver Spoon)

9. Continue adding the sugar, one quarter at a time, taking care to beat it in well after each addition.

10. Beat the buttercream at high speed for 1–2 minutes until fluffy and pale. 

11. Turn the piping bag inside out, then drizzle with strips of the gel colours to create stripes. Turn the bag right side out, then fit it with the star nozzle and fill with buttercream. Clip the bag to keep it all in.

12. Squeeze the buttercream onto the cupcakes. Hold the bag in a vertical position and pipe in a spiral, starting around the outside edge of the case, winding inwards and building height to create a peak.

13. The colour will be blended onto the buttercream, giving a lovely rainbow swirl effect.