Preheat the oven to 180°C.
Rub the flour into the butter and mix in the icing sugar.
Combine whisked eggs and milk with the flour mixture to form a dough.
Wrap the dough in film and freeze for 10 minutes.
Roll out the pastry to 3mm thickness on a floured surface.
Line three tins with pastry, prick the bases, and chill for 15 minutes.
Blind bake for 15 minutes at 180°C using paper and baking beans.
Remove beans and reduce the oven temperature to 150°C.
Mix cream cheese, sugar, soured cream, eggs, yolk, and flour.
Pour mixture into cases, leaving a lip for the sauce.
Add ginger to the 20cm tin, lemon zest to the 18cm tin, and vanilla to the 15cm tin.
Bake the small cake for 30 minutes and the larger ones for 45 minutes.
Heat cream and pour over chocolate and flavoring for each of the three toppings.
Pour cooled toppings onto respective cheesecakes and chill.
Whisk egg whites to soft peaks while heating sugar and water to 120°C.
Slowly whisk the hot syrup into the egg whites until glossy and cold.
Trim excess pastry and place each cheesecake onto its board.
Insert three support straws into the bottom two tiers and trim to height.
Stack the tiers and pipe meringue around the edges.
Decorate with chocolate buttons, popping candy, and crystallised ginger.