SIFT the flour into a large bowl; add the salt and the saffron with its water. Gradually add enough water to make a smooth, pliable dough, kneading vigorously until the color of the saffron is well disbursed and no longer leaves streaks of yellow in the dough.
BREAK off pieces of the dough and roll them into small "sausages" about 4 inch in diameter. Cut these again into short lengths and press them lightly against a fine sieve to make a criss-cross pattern. Spread them out on a large tray sprinkled with flour, and leave them in a dry warm place for 2 days.
BRING a large pan of salted water to the boil. Add the gnocchi a few at a time. Almost as soon as they rise to the top of the pan they are ready. Remove with slotted spoon, let them drain them thoroughly and transfer them to a deep heated serving dish.
DRESS generously with tomato sauce and grated Pecorino cheese, and serve immediately.
FOR this dish it is important that the tomato sauce be well flavored and home-made.