Preheat your oven to 350°F (175°C) and prepare a cake pan with parchment paper and butter.

In a mixing bowl, combine 1.5 cups of flour, 1.5 teaspoons of baking powder, and 0.5 teaspoon of salt; whisk until uniform.

Cream together 0.75 cups of butter and 1 cup of sugar until light and fluffy, about 3–5 minutes.

Add 2 large eggs one at a time, mixing well after each addition until smooth.

Stir in 0.25 cups of sour cream and 1 tablespoon of vanilla until well combined.

Gradually fold the dry ingredients into the wet ingredients until just combined; do not over-mix.

Gently fold in the sliced peaches until evenly distributed throughout the batter.

Pour the batter into the prepared pan and tap lightly to release air bubbles.

Bake for 45-55 minutes until a thermometer reads 210°F (99°C) and the top is golden.

Cool in the pan for 10 minutes before transferring to a wire rack to cool completely.