The Search for the Perfect Gluten Free Vanilla Cupcake - Update!

So, for quite some time now, I've been looking for the Perfect Gluten Free Vanilla Cupcake. I've had a few struggles along the way - such as last week's debacle - but I have finally moved in the right direction with Exclusively Food's Vanilla Cupcakes. Light, fluffy and subtly sweet, these cupcakes are moist - and ironically, are almost identical to my favourite cupcake recipe, Salted Caramel Cupcakes (but without the brown sugar) which manage to keep for a good 3 days!

In the words of Rex Harrison - By George, I think she's got it!

I just bought my very first piping bag, and have done an absolutely terrible job with the piping - please forgive the appalling piping job! These cupcakes look like something out of a Dr. Seuss book (you can eat them on a log; you can eat them with a dog) but taste amazing.

Exclusively Food's Vanilla Cupcakes

You will need:

125 g butter (room temperature)
2/3 C caster sugar
1 tsp vanilla
2 eggs
1 1/4 C self raising gluten free flour
1/2 C milk

1. Preheat the oven to 180 C. Line a 12 hole cupcake tin with cupcake cases.
   
2. Cream butter and sugar together until pale. Beat in vanilla.
3. Beat in 1 egg. Scrape down the sides. Beat in the second egg and scrape again.
4. Mix in the flour in 3 additions, alternating with the milk in 2 additions, mixing continuously.
5. Divide evenly into cupcake cases. Bake for 20-25 minutes or until a skewer comes out clean.
6. Cool on a wire rack.
   

Vanilla SMBC

You will need:

3 egg whites
1/2 C sugar
125 g butter
2 tsp vanilla extract

1. In a large, clean heatproof bowl, combine the egg whites and sugar. Set the bowl over (but not touching) simmering water in a saucepan and heat the mixture, whisking constantly, until the sugar has completely dissolved and the mixture is very warm to the touch. Remove the bowl from the saucepan.
2. Using an electric mixer on high speed, beat the egg white mixture until it is fluffy, cooled to room temperature, and holds stiff peaks (the mixture should not look dry), about 6 minutes.
3. With the mixer on medium-low speed, add the the butter, a few pieces at a time, beating well after each addition. If the icing appears to separate or is very liquid after all the butter is added, continue to beat on high speed until it is smooth and creamy, 3-5 minutes more. Add the vanilla extract scraping down the sides of the bowl as needed.

I've figured out that the big issue is the fat:flour ratio. I'm not sure why the additional fat helps prevent the cakes from going stale, but I've been having a bit of a think about what's going on...

Now this is just some guesswork based on how I know xantham gum and gluten behave chemically... [Beware - sciency bit coming up] In normal cupcakes, the gluten creates a lattice, helping trap the water molecules and preventing them evaporating, leaving them moister for longer. Over time, the water can migrate through the lattice, making the cakes eventually go stale. In gluten free cakes, there a) is no gluten lattice to help trap the cupcakes, and b) the xanthan gum is more soluble in water, meaning that a lattice isn't formed until a later stage during the baking. Adding additional fat a) simulates the moist mouthfeel, and b) helps retain the moisture by forming emulsions (the xantham gum also acts as an emulsifier - or at least, I think it would...). Or I could be completely wrong. Meh - either way - fixing the fat:flour ratio makes a huge difference.

Edit: The Next Day Verdict

As I predicted, these cakes were just lovely the next day. And even - believe it or not - the day after! These cakes were delicious right up until they were all gone - I was incredibly impressed.