Grease with butter a 23 cm round retractable cake tin. Line the bottom with glad wrap and tuck underneath. This is used to lift the Jelly Cheesecake off once set. Grease the sides for easy removal. Grease the glad wrap so that the base does not stick to it.
Break up the biscuits into pieces and put into a food processor and grind them up into fine crumbs
Melt the butter in the microwave for 30 seconds or until fully melted. Combine the butter with the biscuit crumbs in a small bowl until the butter is fully mixed through and the biscuit crumbs stick together.
Place in the bottom of the cake tin and spread with the back of a spoon until the base is fully covered. Using the bottom of a glass. Press the biscuit based firmly all over until evenly flattened. Place in the fridge for 1 hour to set or until firm.
Place the boiling water into a small bowl and sprinkle the gelatine powder over the top, mix with a fork until the gelatine is fully dissolved. Set aside to cool slightly.
In a large bowl add the cream cheese, caster sugar, and vanilla essence and beat with an electric mixer until all is combined and the mixture is smooth. Slowly add the cream and continue to beat. Then add the gelatine and beat until all ingredients are fully combined
Pour the mixture over the top of the biscuit base and spread out as evenly as possible with a spatula. The place in the fridge to set for 4 hours.
Prepare the jelly according to the packet's directions. Set aside to cool and then place in the fridge for 1 to 1 and a half hours. Once the jelly is cold and slightly thick pour over the cream cheese filling and place it back in the fridge until the jelly is set completely. Approx 3 hours.
Once the jelly is fully set, unwrap the glad wrap from the base. Carefully slide a knife along the sides to separate the Jelly Slice from the sides. Slowly release the side of the cake tin, and cut the jelly slice into 12 equal pieces. Use the sides of the glad wrap to lift up the whole jelly slice before cutting if you want to transfer it to a plate before cutting. (Two people may be needed to do this.)