Beat together sugar and eggs. Alternately add flour and buttermilk. Stir in baking soda. Add whipping cream, then margarine. Stir in cardamom. Cook in heart-shaped waffle iron following manufacturer's instructions. Avoid greasing iron; use non-stick cooking spray if necessary. Serve waffles with berry jam. Each waffle contains about: 267 calories; 108 mg sodium; 70 mg cholesterol; 7 grams fat; 45 grams carbohydrates; 6 grams protein; 0.09 gram fiber.