This is my great grandma's recipe...she came from Denmark.
2 C Buttermilk
2 C Flour
3 Eggs
1 tsp baking powder
1/2 tsp salt
1 tsp baking soda
2 T sugar
Beat egg yolks; add sugar, salt, milk, flour, soda, and baking powder (dry ingredients sifted together). Add stiffly beaten egg whites. Bake in butter in a Monk's pan (Aebleskivepande). When half baked, turn with fork and finish baking. Roll in sugar.
May add jelly to center if desired.