Wash in ice water one pound of butter until smooth. To one pound of flour add one-quarter of the butter, one-half teaspoonful cream of tartar, one egg, and one teaspoonful salt; mix all together with ice water (about one-half pint) into smooth dough; let rest awhile, then roll out in a long strip, break the rest of the butter into small pieces the size of a walnut and lay all over the dough, then turn the left end one-third over, then the other end over this; roll out carefully, one-half inch thick, using no more flour for dusting than is necessary, and turn over like American puff paste. Roll five times, and if butter is very rich, you can cut short say one ounce to the pound of flour.