Preheat the oven to 325°F.
Thoroughly grease and flour a 10- to 12-cup Bundt pan, making sure all the grooves are coated.
In a medium bowl, whisk together the 3 cups of flour, baking powder, and salt and cinnamon Set aside.In a large mixing bowl, beat the softened butter and 4 ounces of cream cheese until completely smooth and creamy.
Gradually add the granulated sugar. Continue beating for approximately 5–7 minutes, until the mixture is pale, light, and fluffy. Scrape down the sides of the bowl as needed.Add the eggs one at a time, mixing just until each egg is incorporated before adding the next one.
Mix in the vanilla extract.With the hand mixer , alternate adding the flour mixture and milk
Mix only until everything is combined. Do not overmix the batter.Using a spatula, gently fold the fresh apple mixture into the finished batter.
Spoon the batter evenly into the prepared Bundt pan and smooth the top. Do not fill the pan more than ¾ full.Gently tap the pan on the counter to release any large air pockets.Bake at 325°F for approximately 80 minutes, or 1 hour and 20 minutes.Check the thickest part of the cake with a long wooden skewer. The skewer should come out clean or with a few moist crumbs but no wet batter.
Allow the cake to cool in the pan for 15–20 minutes. Carefully turn it onto a cooling rack and let it cool completely.