Summer-y Key Lime Cupcakes with fluffy marshmallow frosting and a lime curd centre. A treat for a sunny afternoon or days when you need sunshine in your tummy.
Key Lime Cupcakes with Marshmallow Frosting
Can it really be true? Spring is finally here? It’s hard to believe after last weeks frosty temperature but let’s be hopeful!
The first nice days of the year and the hours of sunshine immediately make me think of the summer ahead and I can’t wait to make summer inspired desserts. Ginger beer, ice creams, no bake cheesecakes (after all we don’t need the oven to make the house feel even warmer), milkshakes and so on.
Key Lime Cupcakes with Marshmallow Frosting
One of these desserts, which is a must for me, is anything with coconut and lime. It just screams summer, sunshine and beach even though I am not a massive fan of summer itself.
I like my weather nice and cool so spring and autumn are my favourite.

So lets throw a little pre-summer party and eat delicious Key Lime Cupcakes with a tangy lime curd filling!
Key Lime Cupcakes with Marshmallow Frosting
Key Lime Cupcakes with Marshmallow Frosting
The cupcakes have the perfect balance of texture and sweetness. The sponge itself is a little bit more dense but the light frosting evens that out well. The same goes for the tangy lime curd filling which is soften by the sweetness of the marshmallow frosting. You’ll find yourself eating more than one!

The lime curd is best made on the day before or at least 3 hours before you are planning to bake. It needs enough time to cool down and set.
You can add some lime zest to you sponge batter if you like it will give a nice lime taste to the sponges.

Due to the fresh egg whites in the frosting it will only keep for a day if kept in the fridge. It is best eaten fresh.

The cupcakes cases are from Squires Kitchen and can be found here.

Recipe Key Lime Cupcakes with Marshmallow Frosting

Key Lime Cupcakes with Marshmallow Frosting
Serves 6
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Lime Curd
  1. 225g caster sugar
  2. 4 large eggs
  3. juice of 4 limes
  4. zest of 2 limes
  5. 50g butter
  1. 55g soft butter
  2. 120g caster sugar
  3. 1/2 tsp vanilla bean paste
  4. 1 large egg
  5. 100g plain flour
  6. 100g self-raising flour
  7. 60ml coconut milk
Marshmallow Frosting
  1. 58g egg whites
  2. 1/4 tsp lemon juice
  3. 170g caster sugar
  4. 32.5ml water
  1. A few hours before or on the day before prepare the Lime curd.
  2. Add sugar, eggs, lime juice and butter in a saucepan and cook on medium heat whisking continuously.
  3. Once the whisk starts leaving trails in the curd, remove from the heat and strain it through a sieve.
  4. Stir in the lime zest and leave to cool completely.
  1. Preheat your oven to 180C and line a muffin tray with 6 muffin cases.
  2. In a mixing bowl combine butter and sugar and beat until light and fluffy.
  3. Add the vanilla bean paste and continue beating.
  4. Next add the egg and mix well again.
  5. In a separate bowl sift and combine the flour.
  6. Now add 1/3 flour and some coconut milk and keep alternating between flour and coconut milk until used up.
  7. Spoon the batter in the cupcake cases.
  8. Bake for 20 to 25 minutes until an inserted skewer comes out clean.
  9. Remove from the muffin tray immediately and leave to cool on a wire rack.
  1. Core each cupcake with an apple corer (or a spoon) and fill each cupcake with approx. 2 teaspoons of lime curd.
Marshmallow Frosting
  1. Whisk egg whites and lemon juice to soft peaks.
  2. While whisking the egg whites prepare the sugar syrup.
  3. Combine water and sugar in a saucepan and boil until it reaches 118C to 120C.
  4. With the mixer running slowly pour the syrup in the bowl with the egg whites.
  5. Whisk on high until the meringue is thick and glossy and the bowl is cool to the touch.
  6. Transfer the marshmallow frosting to a piping bag with a nozzle and decorate the cupcakes.
  7. Use a cooks blow torch to brown the marshmallow frosting slightly.
  1. Sponge recipe adapted from Primrose bakery book.
Oh, Sprinkles!

Key Lime Cupcakes with Marshmallow Frosting

Have you got a favourite summer treat? Let me know!