In a medium bowl, cream the sugar with the butter. Beat in the eggs until the mixture is light and lemon colored. Beat in the milk and flour until blended and smooth. Let stand 30 minutes.
Preheat the krumkake iron until a drop of water sizzles when dropped onto the top.
Open the iron; coat lightly with nonstick spray. Spoon 1 tablespoon batter onto center of the hot iron. Close iron. Bake about 1 minute on each side until the cookie is lightly browned. Insert the tip of a knife under the cookie to remove form the iron; roll the hot cookie into a cigar or cone shape. Cool on a rack. Cookies become crisp as they cool. Repeat with remaining batter. Batter will thicken as you use it; add water a tablespoon at a time as necessary to thin it to the consistency of thick cream. Store the baked cookies in an airtight container. They can be kept frozen for several weeks.