1. Chill the tin of evaporated milk in the fridge overnight. 
2. Line a 22x22cm square cake tin with non-stick baking paper.
3. Crush the biscuits in a food processor or add to a large plastic bag and hit with a rolling pin until they turn into fine crumbs.
4. Melt the butter and mix with the biscuit crumbs. Press firmly into the bottom of the cake tin. Refrigerate while you make the cheesecake filling.
5. Add the lemon jelly crystals to a heatproof bowl, add 3/4c of boiling water, 2tsp of lemon zest and 1/4c of lemon juice. Mix well and chill in the fridge until the jelly is slightly wobbly.
6. Add the chilled evaporated milk to a large mixing bowl and beat with an electric mixer until thick, like whipped cream. Refrigerate until required.
7. Soften the cream cheese, add to a large mixing bowl with the sugar. Beat well using an electric mixer until smooth. Add the lemon jelly and beat well until combined.
8. Add the cream cheese mixture to the whipped evaporated milk and beat until combined.
9. Pour over the biscuit base in the cake tin and smooth with the back of a spoon.
10. Cover and refrigerate overnight.
11. Remove the cheesecake from the baking tin and cut into small squares. Refrigerate until ready to serve.
12. Drizzle with the lemon and passionfruit topping to serve
    
     

Tips: 

• Chill the evaporated milk in the fridge over night before you make the cheesecake – this will help it to thicken when beaten.
• You can change the cheesecake flavour by using a different flavoured jelly, e.g. Strawberry.