Recipe from Ida Sacquitne of Decorah, Iowa who demonstrated lefse-making at the Norwegian-American Museum in Decorah and annually for the Nordic Fest. Her father came to Decorah with his parents at age 8 from Voss. "Hard times in Norway caused them to make the move" Use Idaho russett potatoes. Boil, then mash and rice potatoes. Add margarine while potatoes are still warm. Cool until room temperature. Add powdered sugar, flour and salt. Mix with your hands. Knead well and then roll into a log. Cut and measure into 1/3 cup portions and make a round ball of each portion. Press it down by hand and it will be easier to keep round while rolling out. Dust the large canvas-like cloth lefse "board" with flour. Press dough down, turn over and press down again. Roll as thin as possible with a rolling pin with a pastry sleeve into large 14-inch circles to fit lefse grill. The secret of making thin lefse is to use a covered rolling pin. The last roll across dough use grooved lefse rolling pin, which marks the dough slightly and makes it thinner. Use a lefse stick and roll dough on stick and transfer to lefse grill. You must use a lefse stick or holes will be made in the dough. Bake on hot lefse grill or a griddle. Bake a minute or two, then turn with a lefse stick. Turn when bubbles and brown spots appear. Fold each lefse in half or quarters. Cool between towels and store in plastic bag. Spread with butter to eat. Some people sprinkle brown or white sugar on it. Roll up.