Beatrice says that the secret is practice!
Rice the potatoes while they are still hot. Add the cream, the melted Crisco, the salt, and sugar, and mix well. Chill thoroughly, preferably overnight.
Just before baking, add the flour to the potato mixture and mix well. Form the dough into small patties. Keep the patties chilling in the refirgerator, taking them out as you need them.
Roll out the patty with a rolling pin on a floured pastry cloth until very thin. (Beatrice uses a grooved wooden rolling pin with a lightly floured rolling pin cover).
When the Lefse is the desired thickness, grill on a lefse grill set at 500 degrees, flipping constantly until light brown spots appear. (Instead of a lefse grill you can use a griddle set on high).
Cool lefse, cut into quarters, and serve or wrap tightly in plastic wrap. Lefse will keep fresh in the refrigerator for 2-3 days, and freezes beautifully up to 6 months.
Adam Rapoport, editor in chief of Bon Appetit magazine and the website www.bonappetit.com, knows his way around a grill. He has edited an entire book on the subject: The Grilling Book: The Definitive Guide from Bon Appetit.