In a mixing bowl combine flour, oats, baking powder, brown sugar and butter. Press all but 3/4 cup of the crumble mixture into the bottom of a 25cm round cake tin.
Spread the pureed mango over the top and sprinkle with the remaining crumble. Bake for 15 minutes. Remove from oven and let cool for 10 minutes.
In a large bowl beat the cream cheese and white sugar together. Add the vanilla and sour cream and beat until smooth. Beat in the eggs one at a time.
Pour batter into the prepared crust. Place the pan in a large roasting tin and place in the oven. Fill the roasting tin with water to 3cm up the side of the cake tin. Bake 55 minutes. Remove cheesecake from oven, cool to room temperature and refrigerate overnight.