• Preheat the oven to 350°F. Spray a 9×13-inch baking dish with nonstick cooking spray. Set aside.
• In a large mixing bowl, whisk together the flour, sugar, baking powder, cinnamon, and salt.
• To a small bowl, add eggs and oil. Stir until well combined.
• Add the eggs and oil mixture to the flour mixture, mixing until combined.
• Fold in the peaches.
• Pour the batter into the prepared baking dish.

Crumble

• In a medium bowl, whisk together flour, cinnamon, and sugar. Stir in melted butter until a crumbly dough forms.
• Sprinkle the crumble topping evenly over the peach batter.
• Bake for 55-60 minutes, or until a toothpick inserted in the center comes out mostly clean.

Topping

• In the last few minutes of baking the cake, heat the milk, butter, and sugar in a small saucepan over medium heat until the butter and sugar have fully dissolved.
• Take the cake out of the oven and insert a skewer into the top, making between 25-30 spaced holes all the way to the bottom.
• Pour the milk mixture over the cake, making sure it fills the holes and covers the top.
• Let the cake cool completely.

Glaze

• In a medium bowl, whisk confectioners' sugar and milk until smooth. Add more milk if needed, one teaspoon at a time, to reach your desired consistency.
• Drizzle over cooled cake. Serve.