Sprinkle caster sugar on a sheet of greaseproof paper and put on one side.
Sift flour and salt into a mixing bowl and make a well in the centre.
Add the egg and gradually stir in half the milk and water mixture.
Using a whisk blend in the flour from the sides of the bowl.
Beat well until the mixture is smooth.
Stir in the remaining milk liquid and salad oil.
Heat a little oil in a 7 or 8 inch frying pan.
When it is hot pour off any excess oil and spoon about 2 tablespoons of the batter into the pan.
Tip and rotate the pan so that the batter spreads out and thinly covers the bottom of the pan.
Cook the pancake for about 1 minute until pale brown underneath, then turn it over with a palette knife and cook for another minute.
Invert the pancake onto sugared paper, sprinkle with lemon juice and roll up.
Place on a hot serving dish and keep warm whilst making more in the same way