Sift flour, measure, and sift again with the salt, baking powder, and sugar. Cut in the shortening, and add milk to make a soft dough just firm enough to roll. Cover bowl and let dough stand for 30 to 60 minutes; then roll 1 cm thick on lightly floured board and cut in diamond-shaped pieces. Heat about 3 cm of oil in a frying pan to about 370o to 380o. Add a few pieces at a time, turn at once so they will puff evenly, then turn back to brown both sides. Drain on paper toweling. Makes 4 dozen or more.