put the flour in a salad bowl, form a well and put the salt and very small cubes of cold butter in it.
Work the butter and flour with your fingertips and add water in 2 or 3 times .
Press and form a ball of dough .
If it does not form a ball, add a Tbsp water ; if it is too sticky, add a bit flour.
Chill for 30 minutes at least.