Split the trimmed leeks lengthwise, leaving the white root ends whole. Make certain all sand is rinsed away. Bundle leeks and tie with string. Drop into saucepan of boiling water and simmer, covered, about dozen minutes, until just tender. Serve immediately with vinaigrette, or place in iced water to stop cooking, and serve chilled. Food Exchanges per serving: 1 VEGTABLE EXCHANGE + -20ºC AT EXCHANGE; CAL: 76; CHO: Omg; CAR: 8g; PRO: 1g; SOD: 46mg; FAT: 5g;