Sift flour and salt into bowl; make well in center.
Drop in egg yolk; cover with some of flour.
Put lard and water into small pan; heat slowly until lard melts.
Increase heat; bring to boiling point.
Pour all liquid into flour; mix vigorously with wooden spoon until pastry is cool enough to handle.
Use hand to knead until dough is smooth.
Let rest in warm place 20 to 30 minutes; use warm.