These cupcakes are oozing with fresh citrus flavours and are the epitomy of summer flavours! The light and fluffy gluten-free vanilla and key lime sponge is topped with a creamy American buttercream which is packed with even more freshly squeezed key lime juice, making them the ultimate refreshing cupcakes! Take a look below at my simple coeliac-friendly recipe for key lime cupcakes!
How do you make these cupcakes?
So, how are easy are these cupcakes to whip up. Well, we start off by creaming the margarine and sugar together in a mixer until thoroughly combined and a light and fluffy texture has been achieved. It is imperative that the maragrine, even though always softer than butter to start off with, is at room temperature for this, so that the ingredients are incorporated into the batter correctly. Once finished with the creaming method, the eggs are whisked in one at a time until a gloopy mixture forms. Be careful not to ovemix here but we do want them to be whisked in completely! The bourbon vanilla extract is added next and mixed in too. In a separate bowl, the flour, salt, Xanthan Gum and baking powder is sifted together and then slowly added to the wet ingredients and mixed in until just incorporated. We don’t want to overmix and lose those nice airbubbles that we’ve achieved in the previous whisking. The mixture is then scooped into 12 cupcake cases and baked at 160 degrees in a fan assisted oven for around 20-25 minutes until slightly golden and springy to the touch. After cooling, the buttercream is whipped up and piped on, before being topped with fresh key limes!
What equipment do I need for these cupcakess?
- 12-hole cupcake baking tray
- 12 large cupcake cases – I atually use muffin cases (50 x 44mm) because you can really fill them up and have some decent sized cupcakes at the end
- Piping bag fitted with a large open-star tip (Wilton 1M)
What ingredients do I need?
Sugar – White caster sugar adds structure and sweetness to these cupcakes and helps to keep them white during the baking process.
Eggs – Eggs are needed to add structure to the cupcakes and to help them to rise in the baking process, room temperature is essential
Margarine – Margarine works wonders in plain vanilla cupcakes, hence why I’d recommend sticking to a margarine spread like Stork rather than a butter. Unsalted butter can be used at room temperature but you won’t get a super light and fluffy cupcake like you would with margarine
Butter – Unsalted butter is needed for the buttercream and it is essential that it is softened to room temperature beforehand
Gluten-free flour – A gluten-free flour blend which contains a variety of flours is perfect for gluten-free baking. This ensures the cupcakes contain all of the necessary components needed to create the perfect crumb which a gluten-containing flour would natually contain. For these cupcakes I like to use a self-raising flour
Xanthan gum – Xanthan gum is essential for most gluten free recipes and there’s no exceptions here. Doves Farm is my preferred choice but you can use any brand. Xanthan Gum is a gluten replacement for gluten-free baking and helps to replace the lost elasticity that gluten provides, keeping your cupcakes together and stopping them from crumbling into dry pieces later on
Baking powder – Baking powder acts as a leavening agent, helping the cupcakes to rise. Any baking powder will work, just again, check that it is definitely gluten-free as not all brands are.
Salt – A pinch of salt in a recipe enhances the flavours of the other ingredients and offsets the sweetness of the cupcakes. I like to add a pinch of salt to the buttercream too, sounds strange, but trust me, it works!
Double cream – Cream makes the buttercream even creamier! Milk can also be used if you don’t have any cream
Bourbon vanilla extract – A few drops of vanilla extract enhances the flavour of the cupcakes. Vanilla paste can be used too or vanilla from a vanilla pod. I prefer to use a clear liquid extract for this recipe in order to avoid adding any unnecessary yellow tinges to the mixture.
White food colouring – White food colouring helps to reduce any yellow-tinges from the butter used in the buttercream
Icing sugar – Icing sugar or confectioner’s sugar adds the sweetness and structure to the buttercream. It helps the buttercream to set once you’ve piped it into beautiful swirls on your cupcakes
Fresh key limes– Fresh juice, zest and slices of key lime are used to add the zesty fruity notes that these cupcakes are packed full of
Tips & Tricks
Room temperature ingredients are essential for this recipe to work. Room temperature ingredients ensures that they all can be mixed together thoroughly. If you forget to take your eggs out of the fridge beforehand, place them in a bowl of lukewarm, not hot, water 15 minutes prior to baking to bring them to room temperature quickly.
Uniform-sized cupcakes – I like to use an ice cream scoop to spoon my mixture into the cases. This way the cupcakes are likely to have a more uniform size after baking.
The toothpick test is a great way to check whether your cupcakes are done. As all ovens are calibrated differently, the baking times stated are always suggested a a rough guide. To check if the cupcakes are done, insert a tootpick into the middle of a cupcake and if it comes out with no crumbs stuck to it, you can assume that the cupcakes are baked through and ready to come out.
Gel food colouring – It is extremely difficult to achieve a truly white looking buttercream without a bit of gel food colouring to help. Here’s where the science of baking comes in! If you can’t get your hands on a really pale butter or some white gel food colouring, then a few teeny-tiny drops, and with teeny-tiny I do mean a toothpick drop, of purple food colouring will counter-balance the yellow tones of the buttercream, making it appear more white! It sounds bizarre, but it works! Be careful not to over-do the purple as you don’t want to risk accidentally turning your buttercream purple
Key Lime Cupcakes
For the cupcakes
- 230 g margarine room temperature
- 230 g caster sugar
- 230 g gluten-free self-raising flour blend
- 4 large eggs room temperature
- zest from 3 key limes
- ½ tsp baking powder
- ¼ tsp Xanthan Gum
- ¼ tsp salt
- ¼ tsp vanilla extract
For the buttercream
- 250 g unsalted butter softened, room temperature
- 380 g icing sugar sifted
- freshly squeezed juice from 3 key limes
- few drops white food colouring * see notes
- zest from 1 key lime
- 2 tbsp double cream room temperature
- 12 slices key lime freshly sliced
For the cupcakes
- Preheat the oven to 160 C fan and line a 12-hole muffin tray with 12 cupcake cases.
- Cream the margarine on a high speed in a mixer for 2-3 minutes until lighter in colour and fluffy in texture.230 g margarine
- Add the caster sugar and key lime zest, and cream again until completely combined.230 g caster sugar, zest from 3 key limes
- Whisk in the eggs, along with the vanilla extract, one at a time until completely incorporated into the mixture.4 large eggs, ¼ tsp vanilla extract
- In a separate bowl, whisk together the flour, Xanthan Gum, baking powder before adding to the wet mixture. Mix together on a low-medium speed until just incorporated. Try not to overmix!230 g gluten-free self-raising flour blend, ½ tsp baking powder, ¼ tsp Xanthan Gum, ¼ tsp salt
- Spoon the mixture evenly into the 12 cupcake cases and bake in the preheated oven on the middle shelf for around 20-25 minutes or until an inserted toothpick comes out clean.
- Allow the cupcakes to cool to room temperature before topping with buttercream.
For the buttercream
- Cream the unsalted butter in a mixer on the highest setting for around 5 minutes until paler in colour and lighter in texture, scraping down the sides of the bowl as necessary.250 g unsalted butter
- Add the key lime juice, double cream and half of the icing sugar and whisk on the highest setting again until thoroughly combined and no lumps of sugar remain. Scrape down the sides of the bowl regularly to make sure that all ingredients are thoroughly incorporated.380 g icing sugar, 2 tbsp double cream, freshly squeezed juice from 3 key limes
- Continue to sift in the icing sugar in batches and whisk up until the buttercream aquires a light and fluffy texture. Add a few drops of white or purple food colouring and whisk again until completely incorporated. If the buttercream is too stiff for piping, add another teaspoon of double cream to loosen. If the opposite occurs, add a tablespoon of icing sugar at a time to thicken.few drops white food colouring
- Transfer the buttercream to a piping bag fitting with an open-star nozzle such as the Wilton 1M and pipe in a blob on the centre of each cupcake, before continuing to pipe in swirls around the cupcake. Top with freshly grated key lime zest and a slice of key lime to finish.zest from 1 key lime