Fool proof food
Sieve the rice flour, fine ground cornmeal, potato flour, salt and xanthan gum into a pyrex bowl and mix well.
Cut the butter into cubes and gently rub into the flour mixture.
Make a well in the centre on the pyrex bowl and carefully add in some of the egg/water mixture, using a fork to bring the pastry together.
It is tempting to add more liquid at this stage but try not to, as it is very easy to make the pastry too wet.
On a very lightly rice-floured board, gently knead the dough with the heel of your hand for a few minutes to form a silky smooth ball of dough.
Flatten slightly, wrap in cling film and refrigerate for a least 1 hour.
When it has chilled enough, roll out the pastry (I find putting it between 2 sheets of bakewell paper stops it sticking) and line the tart tin.
