Lemon cupcakes with lemon Italian meringue buttercream

Ever since I ate a cupcake with  Italian meringue buttercream, I knew I had to learn to make it. It was so creamy and light and grown up – less like icing and more like the nicest mousse in the world. The thing is, it really difficult to make – it uses Italian meringue (boiling sugar poured and whisked into egg whites to cook them), you need a sugar thermometer and to handle boily sugar without melting your skin off.  On the surface of it, these cupcakes look pretty simple but actually the icing has taken a lot of fiddling and practice to get them right. The first test I did, there seemed to be too much butter in the recipe I used and I poured in the boiling sugar incorrectly so it clumped at the bottom. The second attempt (this one) was much better.


To make the buttercream you are going to need a stand mixer – I think you might be able to try it with a hand whisk but I needed two hands to get the boiling sugar in safely whilst whisking all the time. I have a Kenwood KMix (a beautiful white one which goes with my shiny white kitchen) which is probably my most used kitchen item, I turn it on at least 3 or 4 times a week. We do bread, pizza dough, biscuits, cake, brownies etc. in it.  It had been a toss up between that and an Artisan but I think the Artisan looks a bit twee, it is much more expensive for almost no additional benefit and my granddad worked for Kenwood his whole life so I have some deeply rooted brand loyalty,  Isn’t it beautiful? I still tell it that I love it from time to time.


Anyway on to the cake – I made lemon sponge with a lemon curd centre, lemon italian meringue buttercream and homemade chocolate buttons on top.

For the buttercream (this makes enough for about 24 cakes; it is worth making lots and then freezing the rest if you are doing less cakes)

Basic Recipe

  • 375g white caster sugar
  • 1 tbsp golden syrup
  • 100ml water
  • 6 egg whites
  • 600g soften unsalted butter in 2cm-ish chunks

For lemon curd buttercream add:

  • Zest of 2 lemons
  • Juice of two lemons
  • 3 tbsp of Lemon Curd


  1. Put sugar, golden syrup and water in a medium heavy bottomed saucepan and stir until totally combined.  Brush the inside of the saucepan with clean water on a damp pastry brush to dislodge any stray grains. Set over high heat and bring to a rapid boil. When the sugar mixture has come to the boil add a sugar thermometer and keep cooking until it reaches will into soft ball stage, 121°C.
  2. Meanwhile put the carefully separated egg whites in the bowl of an electric mixer (with a whisk attachment) and whisk the egg whites to soft peaks – be careful not to over whisk. Then slowly pour a steady stream of sugar syrup into the egg whites, being careful not to hit the whisk while doing so – I find pouring down the side of the bowl is the easiest way of doing this. Continue whisking until sides of the bowl feel cool. Add the softened butter chunk at a time one by one at a time and whip until fully incorporated and smooth
  3. Mix in zest, juice and lemon curd for lemon flavour icing.

For the cake (makes about 16)

  • 250g unsalted softened butter
  • 250g golden caster sugar
  • 250g self-raising flour
  • 4 eggs
  • Zest of 1 lemon
  • Juice of 1 lemon

For the filling

  • Jar of Lemon Curd

For the buttons

  • White chocolate


  1. Pre-heat your oven to 180c (I have always used an oven thermometer to check because most ovens are way out – except my brand new oven. That is perfect) and put some cases in a muffin tin or two
  2. Beat together the butter and sugar until pale and creamy, then add the eggs, one at a time, beating thoroughly after each one. Sift in the flour and then add the lemon zest and the juice of one lemon and mix until well combined.
  3. Spoon it into the cupcake mix into the cases for about 2/3 full. I use an ice-cream scoop (I have 3 in different sizes and this ensures they are all exactly the same)
  4. Bake for about 15 – 18 ish minutes but keep an eye on them from around 12 minutes
  5. When they are beginning to look golden and are springy to the touch they can come out
  6. For the filling, core out your cupcakes using either a corer or a sharp knife, put a teaspoon of lemon curd in each one and replace the tops
  7. To make the chocolate buttons, gentle melt the white chocolate and pour into silicone button mold like this one from Amazon