Place the butter, salt and water in a saucepan, then place on the heat.
Bring to a boil.
Remove from heat and pour all the flour in one go.
Stir with a wooden spatula, making sure that lumps do not form.
The resulting dough is called 'panada'. Dry off the panada on the heat, stirring with a wooden spatula, until the pastry comes away from the sides of the saucepan and forms a ball.