Put the flour in a bowl, and make a hollow in the middle of the flour; put into it a pinch of salt, a few drops of water and the yolk of an egg.
Stir with a wooden spoon, adding gradually whatever liquid you have decided to use.
The batter should be runny, but should still cling to the spoon.
If lumps form, use an egg whisk.
Then add the oil, mixing well.
Leave the batter to rest for 1 to 2 hours.
A few minutes before preparing whatever it is you are going to fry, whip a white of egg stiffly and stir it in gently.
If you want extra-special fritters, either sweet or savory, then, when you add the oil, mix in also a generous tablespoonful of cognac, rum or brandy.