Lefser at Norwegian Folk Museum:
250 grams sugar
125 grams melted butter
1/2 liter buttermilk
1 teaspoon "hjortetakksalt" (salt of stag's horn - I have no idea what the substitute for this is but some clever commenters say it's ammonium carbonate)
1 kg flour
Mix egg, sugar and butter. Add milk. Mix the hjortetakksalt with the flour before adding it as well. Mix dough until thick enough to roll out with rolling pin. Cakes should be somewhat thick. Use barley flour to flour the rolling surface. The rolling pin used is usually textured like this one.
Fry the lefser on a griddle or a dry frying pan. Serve DRENCHED in butter.