Line two x 12-hole cupcake tins with cupcake cases (large).
Pre-heat the oven to 180 C/350 F/Gas 4.
Weigh and mix together the flour, xanthan gum, bicarbonate of soda, baking powder, and salt. TIP : weigh into an airtight container and shake well to blend. Set aside.
Weigh or measure the milk into a jug and add the white wine vinegar. Stir thoroughly and leave to stand at room temperature for 10 to 15 minutes, until it has a slightly curdled appearance. This will make 'buttermilk'
Sift the cocoa powder into a small bowl. Add the boiling water a little at a time, gently stirring through until you have a smooth paste. Set aside.
In a large bowl, cream the butter with the sugar using an electric whisk until pale and fluffy.
Break the eggs into a small bowl and beat with a fork to blend, before gradually adding a little at a time to the butter mixture, beating thoroughly between each addition.
Add the vanilla extract and cocoa paste and beat again, until smooth and well-blended.
Gently fold in the ground almonds using a large spoon or spatula.
Finally add and fold through the dry ingredients and milk mixture, alternating a little dry followed by a little 'buttermilk' (about a third of each at a time). Fold gently to ensure as much air remains as possible and stop when the ingredients are JUST amalgamated to avoid over-mixing.
Spoon the mixture equally into the cupcake cases (about half to two-thirds full) and smooth the tops with the back of a teaspoon.
Bake for 15-20 minutes until a skewer comes out clean and the tops are soft and spring back.
Remove from the oven and leave to cool in the tins for 5 minutes before transferring to a wire rack. Allow to cool completely before decorating.
* Note: nutritional information is an estimate & may vary according to portion size/ingredient variants.Gluten Free Alchemist Rice Free Flour Blend A can be found on the GFA Flours & Flour BlendingPage. This sponge can be made a couple of days in advance and will mature nicely. Keeps well for several days at room temperature in an airtight container. Freezes well.If decorated with cream or anything that requires refrigeration, bring to room temperature for half an hour or so before serving.