Set the oven temperature to 350 degrees F before using.
In a medium-sized bowl, combine the butter and 1 cup of sugar. Use an electric mixer on medium speed to beat the mixture until it becomes smooth and fluffy.
Put the mixer on low speed and incorporate the eggs individually.
Combine sour cream and vanilla and stir until the mixture is creamy and without any lumps.
Combine the flour, baking soda, baking powder, and salt in a separate bowl.
Using the lowest setting on the mixer, gradually incorporate the dry ingredients into the wet mixture and stir until they are just blended together.
Mix the nutmeg or cinnamon with the remaining 1/2 cup sugar in a small bowl.
Place half of the batter evenly on the bottom of a 9x9 pan. Layer half of the peaches on top, and then sprinkle 2/3 of the sugar mixture over them.
Evenly distribute the remaining batter over the top, then layer on the remaining peaches and generously sprinkle with the remaining sugar.
Cook for around 55 to 65 minutes or until the center is firm and doesn't wobble, or when a toothpick inserted into the middle comes out clean.
Notes
Use High Quality Ingredients: The quality of your ingredients, especially the peaches, will significantly impact the taste of your coffee cake. Choose ripe, juicy peaches for the best results.
Replace Liquid with Coffee: For an extra coffee kick, consider replacing some of the liquid in the recipe with brewed coffee. It adds a delightful depth of flavor.
Different Spices: Experiment with different spices like nutmeg or ginger to give your coffee cake a unique twist. These spices will complement the peaches beautifully.
Fruit: Make a blueberry coffee cake or make this cake with any seasonal fruit.