1. Pour milk into medium saucepan; sprinkle surface evenly with gelatin and let stand 10 minutes to hydrate gelatin. Meanwhile, turn contents of two ice cube trays (about 32 cubes) into large bowl; add 4 cups cold water. Measure cream into large measuring cup or pitcher. With paring knife, scrape vanilla seeds into cream. Place pod in cream along with seeds, add julienne lemon peel, and set mixture aside. Set eight wine glasses or 4-ounce ramekins on baking sheet.

2. Heat milk and gelatin mixture over high heat, stirring constantly, until gelatin is dissolved and mixture registers 135°F on instant-read thermometer, about 1 1/2 minutes. Off heat, add sugar and salt; stir until dissolved, about 1 minute.

3. Stirring constantly, slowly pour cream mixture into saucepan containing milk, then transfer mixture to medium bowl and set bowl over ice water bath. Stir frequently until thickened to consistency of eggnog and mixture registers 50°F on instant-read thermometer, about 10 minutes. Strain mixture into large measuring cup or pitcher, stir in lemon juice, then distribute evenly among wine glasses or ramekins. Cover baking sheet with plastic wrap, making sure that plastic does not mar surface of cream; refrigerate until just set (mixture should wobble when shaken gently), 4 hours.

4. Serve panna cotta in wine glasses, or following illustrations 1 through 4, unmold panna cotta from ramekins and serve immediately.

Serves 8