In a mixing bowl stir together the flour, lemon peel, baking powder, salt, and cardamom. in a mixing bowl beat the margarine or butter with an electric mixer on medium to high speed for 30 seconds. Add sugar; beat till thoroughly combined. Add eggs; beat till fluffy. Stir in the flour mixture. Turn out onto a lightly floured surface. Knead for 10 to 12 strokes or till dough clings together. Roll dough into a log about 1-1/2 inches in diameter.

In a wok or 3-quart saucepan heat 1-1/2 to 2 inches of cooking oil or shortening to 365°. Meanwhile, cut dough into 1/2-inch slices. Roll each slice into a ball. Stir together the egg white and the water. Roll each ball in the egg white mixture, then in sesame seeds to coat lightly.

Fry balls of dough, a few at a time, in hot oil for 3 to 5 minutes or till golden brown and balls begin to expand and crack, turning once. Using a wire strainer or slotted spoon, remove balls from hot oil. Drain on a wok rack or on paper towels. Keep warm in a 300° oven while frying remaining balls. Serve warm.