1. Beat eggs with sugar in a medium-size bowl with electric mixer at high speed until very thick and lemon-colored. (Beating will take 5 minutes don't underbeat.)
2. Sift flour and cardamom onto wax paper.
3. Add flour mixture, alternately with cream, to bowl.
4. Heat krumkake iron in its holder, to moderately hot on top of range (a few drops of water will dance about). Do not allow to become too hot.
5. Drop about a tablespoon of batter on hot iron; bring cover down; do not press hard. Cook, over moderate heat, 30 seconds on each side of iron; peel cookie carefully from iron with a spatula; quickly roll around handle of a wooden spoon or form (which may come with your krumkake iron). Cookie will stiffen at once. Remove from spoon handle or form. Continue with remaining batter.
6. Store cookies in an airtight container (they keep very well). They can be served as is, or filled with flavored whipped cream and a few fresh berries just before serving.