Heat the krumkake iron on the stove over medium heat, or use an electric krumkake or pizzelle iron.
In a bowl, cream together the butter and sugar.
Add the eggs one at a time, mixing well with a spoon.
Pour in the milk, flour, vanilla extract, and optional butter flavoring.
Mix until well combined.
Place a teaspoon of batter on the preheated iron and press together.
Cook until browned, approximately 30 seconds per side, depending on the heat.
Remove from the iron and quickly roll up the krumkake around a stick or cone before they harden.
