• Preheat the oven to 350-degrees Fahrenheit (175-degrees Celsius).
• Liberally spray a 9" springform pan with baking spray and set aside. *Note - When baking you may want to place the springform pan on a baking sheet, but that's optional.

To make the cake:

• In a large bowl, cream together the softened butter and granulated sugar.
• Add the eggs, one at a time, to the creamed butter and sugar along with the vanilla extract. Set aside.
• In a medium bowl, whisk together the flour, baking powder, and salt.
• Use a spatula to gradually stir the dry ingredients into the wet ingredients. Switch to a hand mixer (or stand mixer) and blend until the batter is fully incorporated and smooth. *Note - this will be a thick batter.
• Spoon the batter into the prepared springform pan and spread the batter evenly throughout the pan. *Note - spraying the spatula with baking spray will prevent excessive sticking of the cake batter to the spatula.
• Add the cored and sliced apple rounds to the top of the cake batter, and gently but firmly press them partially into the batter.
• Bake the cake in the preheated oven for 40-45 minutes or until the cake is golden brown and a cake tester inserted in the center comes out clean.
• After baking cool the cake on a wire rack for 40 minutes. After 40 minutes remove the springform collar and allow the cake to completely before glazing.

To make the glaze:

• Whisk all the ingredients in a medium-sized bowl until smooth and creamy. Add additional milk (1 teaspoon at a time), if you prefer a thinner consistency.
• Drizzle the glaze liberally onto the cooled cake and serve cake slices with additional glaze if desired.