Preheat the oven to 300°F/150°C. Grease a large Bundt or tube pan generously with cooking spray and set aside. Place half of the peach slices on the bottom of the pan in a single layer; set aside.
In a small bowl, combine brown sugar, cinnamon, and nutmeg. Sprinkle half the sugar mixture on the peach, followed by melted butter and bourbon. Cream the butter and sugar at high speed in a stand mixer or using a hand mixer until it’s fluffy and looks white, 3-5 minutes.
Then add cream cheese and continue mixing for two more minutes. Stir in the eggs, a little at a time, beating the mixture well between each addition.
Mix flour, baking powder, and salt into the batter, followed by vanilla extract and milk. Stir well until everything is thoroughly combined. DO NOT overmix. Scrape down the sides of the mixing bowl.
Spoon half of the batter over the peach slices and spread it out with a spatula. Then layer the remaining peaches on the batter; sprinkle with the remaining brown sugar mixture, and top with the remaining cake batter.
Tap pans on the work surface to eliminate large air bubbles. To be on the safe side, place it on a baking tray just in case you have any spills.
Bake at 300℉/150℃ until a tester inserted into the center comes out clean, 60 minutes or more. Transfer to a plate and let it cool. While the cake is baking, make the icing.
Whisk together confectioners' sugar, vanilla extract, and milk, adding a few drops more milk as needed to make the glaze smooth and pourable.
Drizzle as much as you like over the cake with a fork or spoon. Slice and serve.