Method

1. Preheat the oven to 180C/350F/Gas 4 and line a 12-hole bun tin with 12 paper fairy cake cases. (Or for deep American-style cupcakes, line a 6-hole muffin tin with larger muffin cases.)

2. Place the softened butter in a large bowl then beat with an electric hand-whisk until pale and fluffy. Gradually add the sugar and continue to beat until fully combined.

3. Add a little of the beaten egg to the butter mixture, then whisk again. Gradually add the egg, little by little, whisking after each addition. It’s important to go slowly here, as adding too much egg at once can cause the mix to split. If it does split, simply add a tablespoon of the flour and whisk until the batter is smooth again.

4. Sift the flour into the bowl. Using a large metal spoon or spatula, fold the flour into the cake mix.

5. Add the vanilla and the salt and stir to combine. Add the milk to get the cake mix to a soft dropping consistency, where a heaped spoonful of mixture falls off the spoon after tipping it for few seconds.

6. Using two dessert spoons (one to scoop and the other to push the mix into the tin), fill the paper cases half full with the batter, filling them equally.

7. Bake the fairy cakes for 15 minutes in the middle of the oven, until golden-brown and the cakes spring back when pressed lightly. (Bake cupcakes for 18-20 minutes.)

8. When cool enough to handle, lift the cakes onto a cooling rack and leave to cool completely. The cakes can be frozen for up to a month, or will keep fresh in an airtight tin for a few days.

9. To make the buttercream, put the butter into a large bowl and beat with electric hand beaters until smooth and creamy. Sift in the icing sugar, then work it into the butter, starting slowly at first, then beating more vigorously once all the sugar is combined. Add the milk and the vanilla, then beat until creamy and smooth. If the mixture is too stiff, add a little more milk. You can colour the buttercream at this stage.

10. To make butterfly cakes, cut the top off each cake using a small serrated knife – angling the knife in slightly so that you make a concave cut. Cut the tops in half, to make two ‘wings’. Spread or pipe a heaped teaspoon of buttercream into the dip you have made in the top of each cake, and spoon on a little lemon curd or jam. Place the wings into the buttercream, and dust with a little icing sugar.