Begin by boiling potatoes until they are fork tender. Note: I like to cook them in the microwave to prevent them from retaining too much moisture. You don't want soggy potatoes, or your lefse will be too soft to roll out!
Rice your potatoes into a large mixing bowl. Alternatively, you can mash them until smooth. You will end up with about 3-3 1/2 cups of riced potatoes.
Add the sifted AP flour, salt, sugar, melted butter, and 2 Tablespoons of heavy cream. Mix together with your hands until the dough forms. Add cream 1 Tablespoon until the dough is similar to the consistency of Play-Doh. Depending on how much moisture is in your potatoes, you may need up to a 1/2 cup.
Dust a pastry board with flour. Form the dough into 3 Tablespoon balls. This recipe will make about 18 lefse. Flatten each ball into a smooth disc. Roll with a rolling pin into a very thin circle. When you pick up the lefse, you should be able to see your hands through the dough.
Heat a griddle or pan over medium heat. Place each lefse on the griddle or pan, cooking for a couple minutes on each side until thoroughly cooked through and small brown spots begin forming. Don't overcook or you will end up with very brittle lefse. Keep lefse covered in a linen or kitchen towel to prevent them from drying out. I like to double cover them with parchment paper and a linen!
Serve lefse with butter, sugar, cinnamon, jam, meatballs, deli meat, and anything else you like. Store the lefse wrapped in a towel in an airtight bag or container.