In a large saucepan, gently heat the cream just below the scald point. Add the sugar and gelatin, when it is dissolved, add the grated lemon and the lemon juice. Simmer for 10 minutes. Stir frequently. When mixture begins to thicken pour into individual serving ramekins. Put them on a tray and refrigerate for several hours.
You can either leave them in the molds, or run a knife around the outside of the mold, invert and tap the bottom of the mold to release.
Top with your favorite topping, suggestions include chocolate sauce, fresh berries, or caramel.
Note: If I actually explained the definition of panna cotta, nobody would ever find it appetizing. But it actually is quite good. Make it and try for yourself.