Blackberry Cheesecake

Put the first lot of ingredients into a mixing bowl and whizz with an electric mixer until absolutely smooth.

Then crush the 16 biscuits - a rolling pin and a flat surface will do it in seconds - scoop them into a bowl, and mix with the cinnamon and the butter.

Next press the biscuit mixture all over the base of the tin, bringing it up about 1cm at the edges.  Pour the cheese mixture in now and bake for about 30-40 minutes, or until firm and set in the centre; then turn the oven off and leave the cheesecake there till cool. 

The blackberries should be washed and simmered with the caster sugar (but no water) for a very few minutes, then drained in a sieve over a bowl.  Add the arrowroot-and-water mixture to the juice, bring to the boil and boil until thickened.  Mix the thickened juice with the fruit and top the cake with the mixture when cool.  Press some more biscuit crumbs all round the edges.  Serve only when thoroughly chiled.

Note:  You can, of course, use other toppings.  Blackcurrante are particularly nice, or fresh raspberries or strawberries - in season.