Preheat oven to 350F/160C/gas mark 4. Process cereal or nuts and half the salt into fine crumbs in food processor or blender. Add melted margarine, and pulse to combine. If using a blender, put the mixture in a bowl, then add margarine and stir until well-mixed. It should hold together and not be too dry.

Press the mixture evenly into the bottom and halfway up the sides of 9" springform pan. Use a piece of waxed paper to help you press it evenly. Bake 10 minutes, then set on a cooling rack. Leave the oven on.

Purée all the remaining ingredients in a food processor or with a mixer for 3 to 5 minutes until very smooth.

Pour into crust, and bake 70-75 minutes, or until filling is set and the top cracks slightly. Cool on a wire rack, then chill completely in refrigerator, at least 3 hours or overnight. Run a knife around the inside of the cheesecake before releasing the pan. Slice and garnish each serving with candied pumpkin seeds (recipe follows) or candied cranberries.

If using whole seeds from a pumpkin, rinse them well and remove all the strings, then cover with well-salted water and boil for 10 minutes. Rinse and drain.

If using shelled seeds, skip the first step. Mix the other ingredients together and bring to a boil in a saucepan for one minute. Stir in the pumpkin seeds.

Pour the mixture onto a rimmed baking sheet covered with foil or parchment paper. Bake 20-30 minutes at 325F/140C/gas mark 3, stirring every 10 minutes and keeping the seeds spread apart so the syrup can thicken. These can burn easily, so pay attention.

Remove when golden brown and set the tray on a cooling rack. When they are cool, they will harden into a brittle. Break up into pieces and serve as a garnish with the cheesecake or eat as a snack.