Preheat the oven to 325 degrees Fahrenheit (163 degrees Celsius). Thoroughly grease and flour a 12-cup bundt pan.
In the bowl of a stand mixer, combine the butter, oil, vanilla, and cream cheese and beat on high until well combined (2-3 minutes).
1½ cups unsalted butter, 2 tablespoon avocado oil, 2 teaspoon vanilla extract, 8 ounces cream cheese
Slowly add the granulated sugar to the bowl and beat on high until very light and fluffy (about 6-8 minutes).
2¾ cups granulated sugar
Add the eggs one at a time, beating well after each addition. Scrape down the sides of the mixing bowl as needed.
6 large eggs
Turn the mixer down to low and add the flour slowly. Once combined, add the cinnamon and salt to the bowl and beat on low speed until just combined.
3 cups cake flour, ½ teaspoon ground cinnamon, ¼ teaspoon salt
Fold in the diced peaches until they are evenly distributed throughout the batter then set the bowl of batter aside.
1½ cups diced peaches
Layer the sliced peaches in the bottom of the bundt pan.
2 medium peaches
Prepare the topping by combining the brown sugar, butter, and cinnamon in a small bowl. Stir until everything is well combined then pour the mixture over the sliced peaches in the bundt pan.
¼ cup butter, ½ cup light brown sugar, ½ teaspoon ground cinnamon
Gently pour the cake batter into the bundt pan, making sure to evenly distribute it over the peaches and topping. Make sure that you fill your pan no more than ¾ full.
Place the cake in the preheated oven and bake for 55-70 minutes or until a toothpick inserted into the center of the cake comes out clean. Cook time may vary, so begin checking for doneness at the 50-minute mark.
Once the cake is done baking, let it cool in the pan for 10-15 minutes before turning it out onto a wire cooling rack.
While the cake cools, prepare the glaze by combining the confectioner's sugar, milk, and vanilla extract in a medium-sized bowl. Whisk until smooth.
1 cup confectioner's sugar, 2-3 tablespoon milk, 1 teaspoon vanilla extract
Drizzle the glaze over the cooled cake, then slice and serve. Enjoy!