In a medium saucepan, combine the halved cherries and granulated sugar over medium heat. Stir gently until the mixture comes to a boil, and let it simmer for about 5 minutes until thickened and glossy. Remove from heat and allow to cool slightly before blending it until smooth.

Next, crush the Oreo cookies finely and combine with brown sugar and melted unsalted butter. Press this mixture into the bottom of a greased 9-inch springform pan and chill in the refrigerator for 30 minutes.

While the crust is chilling, beat the softened cream cheese until smooth. Gradually add in caster sugar, sour cream, powdered sugar, milk powder, and vanilla extract, beating until light and fluffy.

In a separate bowl, whip the heavy cream until stiff peaks form. Gently fold the whipped cream into the cream cheese mixture in three additions.

Spread half of the cheesecake filling over the crust, drizzle some cherry sauce, and swirl. Pour in the remaining filling and top with more cherry sauce.

Cover the cheesecake and refrigerate for at least 6-8 hours. Avoid freezing.