Preheat your oven to 350°F (175°C) and line a standard cupcake pan with paper liners.

In a large bowl, cream together the softened butter and granulated sugar using an electric mixer for about 2-3 minutes until light and fluffy.

Add the eggs one at a time to the butter-sugar mixture, beating well after each addition, then mix in the vanilla extract until smooth.

In another bowl, whisk together the flour, baking powder, ground cinnamon, and salt. Gradually add to the wet ingredients, alternating with the milk.

Gently fold in the chopped ripe peaches until evenly distributed in the batter.

Fill each cupcake liner about two-thirds full with the batter.

In a separate bowl, mix together the brown sugar, flour, rolled oats, ground cinnamon, and melted butter to create a crumbly topping.

Sprinkle the crumb topping over each filled cupcake liner.

Bake in the preheated oven for 18-20 minutes, until golden brown and a toothpick inserted in the center comes out clean.

Let the cupcakes cool in the pan for about 5 minutes before transferring to a wire rack to cool completely.