2. In 1-quart saucepan, combine cream, sugar, lemon peel, cinnamon stick, and vanilla bean halves and seeds (do not add vanilla extract); heat to boiling over high heat, stirring occasionally. Reduce heat and simmer, stirring occasionally, 5 minutes. Stir in milk mixture; cook over low heat, stirring frequently, until gelatin has completely dissolved, 2 to 3 minutes.

3. Discard lemon peel, cinnamon stick, and vanilla bean from cream mixture. (Stir in vanilla extract, if using.) Pour cream mixture into medium bowl set in large bowl of ice water. With rubber spatula, stir mixture until it just begins to set, 10 to 12 minutes. Pour cream mixture into eight 4-ounce ramekins. Place ramekins in jelly-roll pan for easier handling. Cover and refrigerate panna cotta until well chilled and set, 4 hours or up to overnight.

4. Meanwhile, prepare Raspberry Sauce. Into a non-reactive 2-quart saucepan, with back of a spoon, press raspberries through a fine sieve. Discard seeds. Stir in the jelly and cornstarch. Heat over high heat until boiling, stirring constantly; boil 1 minute. Serve at room temperature or cover and refrigerate for up to 2 days.

5. To unmold panna cotta, run tip of knife around edges. Tap side of each ramekin sharply to break seat. Invert onto plates. Spoon Raspberry sauce around each panna cotta and sprinkle with raspberries.