Preheat your oven to 350°F (175°C) and grease an 8x8 or 9x9 inch baking dish with unsalted butter or non-stick spray.

In a large mixing bowl, cream the softened unsalted butter and granulated sugar together on medium speed for about 3 minutes until light and fluffy.

Incorporate the large eggs one at a time, mixing well after each addition, then stir in the vanilla extract.

In a separate bowl, whisk together the all-purpose flour, baking powder, and salt until evenly mixed.

Gradually add the dry mixture into the wet mixture, alternating with the milk, mixing until just combined.

Gently fold in the chopped peaches to ensure even distribution.

Transfer the batter into the prepared baking dish, smoothing the top evenly.

Place in the preheated oven and bake for 40-45 minutes, checking for doneness with a toothpick.

Allow the cake to cool in the pan for about 10 minutes, then transfer to a wire rack to cool completely.

For the glaze, whisk together powdered sugar and a splash of milk until smooth, adjusting consistency as needed.

Drizzle the glaze over the cooled cake, slice, and serve.