Preheat the oven to 350 degrees F. Lightly grease a 9X13-inch baking dish with cooking spray and set aside. In a medium or large bowl, combine the flour, baking powder, salt, sugar and cornstarch. Blend. Make a well in the center and add the vanilla, eggs, milk and melted butter. Whisk together until well combined. Spread the batter evenly in the prepared baking dish.
Drain the can of peaches, saving the juice. Scatter them over the top of the batter evenly. In a medium bowl, beat the cream cheese, sugar and reserved peach juice together until light and creamy. Dollop the cream cheese mixture in tablespoon-sized spoonfuls over the top of the batter and peaches and then use a spatula to evenly spread together to form a creamy layer. Sprinkle the top of the cream cheese layer with cinnamon and sugar. Bake for 45-60 minutes until the edges are puffed and golden and the cream cheese layer has bubbled slightly on top.