In a food processor or a ziploc bag crush the biscuits into fine crumbs. Add melted butter and pulse until combined. Press into bottom of 9-inch (23cm) springform pan. Refrigerate while making the filling.
Mango puree: (if you using canned mango skip to the nest step): cut mango into cubes and place in a food processor or a blender. Blend until completely smooth. Divide into 2 portions, 500 grams (17.6oz) and 300 grams (10.6oz). Set aside.
In a small bowl stir gelatin powder and water. Let bloom for 10 minutes.
In a large bowl beat cream cheese until soft and smooth, add heavy cream, vanilla extract and beat to soft peaks.
Melt the white chocolate in the microwave, stirring after every 20 seconds until completely melted and smooth.
Pour melted white chocolate into the bowl, and the bigger portion of mango pulp (500g), lemon juice, lemon zest and beat until combined and smooth.
Melt the gelatin in the microwave for 15 seconds. Temper the gelatin: Gradually add few tablespoons of the cheesecake mixture into the dissolved gelatin and stir until combined. Pour back to the cheesecake mixture and mix until combined. Pour into the springform pan and freeze while making the topping.
Mango jelly: In a small bowl stir gelatin powder and water. Let bloom for 10 minutes. In a small sauce pan place 300g mango pulp, water and sugar. Cook over medium-high heat, stirring occasionally until the sugar is dissolves. Remove from heat and add bloomed gelatin. Stir until the gelatin is melted and incorporated. Let cool to room temperature and pour over the cake.
Refrigerate the cake overnight.