Preheat the oven to 160°C (320°F). Place the square baking pan inside the roasting pan and boil enough water for the water bath.

Combine the crushed digestive biscuits with 60 g melted butter in a mixing bowl until all crumbs are moistened.

Press the biscuit mixture firmly and evenly into the base of the square baking pan.

Whisk the cream cheese, sour cream, caster sugar, salt, and vanilla extract in a clean mixing bowl until smooth.

Add the 2 eggs one at a time, whisking after each addition only until incorporated.

Whisk in the whipping cream, corn flour, and lemon juice until the cheesecake batter is smooth.

Pour the cheesecake batter over the prepared biscuit base and level the surface with a rubber spatula.

Spoon mango purée over the batter, then drag a skewer through it to create decorative swirls.

Pour hot water into the roasting pan around the square baking pan, keeping the water below the rim of the cake pan.

Bake the cheesecake in the water bath at 160°C (320°F) for 20 to 25 minutes, until the edges are set and the center has a slight wobble.

Remove the square baking pan from the water bath and cool the cheesecake completely at room temperature.

Demould the cooled cheesecake and slice it into 9 squares before serving.