Grease a 16cm (6 inch) loose bottomed and spring form cake tin with melted butter and then line with parchment paper.
Crush the shortbread biscuits by pulsing them in a food processor or put them in a plastic bag and hit them with a rolling pin. Stir in the melted butter. Put into the bottom of the cake tin and press down to make a smooth and even base. Put in the fridge to firm up for an hour.
When you are ready to complete the cheesecake sieve the icing sugar into a bowl and add the cream cheese, vanilla extract and lemon juice. With an electric whisk beat the mixture until it becomes thick.
Spoon the mix over the biscuit base, making sure the top is even and smooth. Put in the fridge to set for an hour.
Spread the strawberry jam over the top of the cheesecake and return to the fridge.
When you are ready to serve remove the cheesecake from the tin, peel away any paper and enjoy!