Preheat oven to 350 degrees F (180 degrees C).
In a saucepan over medium heat, add Peach (4 pound), Caster Sugar (1/2 cup), Ground Cinnamon (1/2 teaspoon), and Lemon Juice (1 tablespoon), stir to combine and bring to a boil. Cook for few minutes until the peaches soften a little bit. Set aside.
In a cast iron skillet or a 13-by-9 inch baking dish, add Butter (1/2 cup). Place it in the oven to melt.
In a large bowl, add All-Purpose Flour (1 cup), Caster Sugar (3/4 cup), Baking Powder (2 teaspoon) and Salt (1/2 teaspoon). Whisk together. In a jug whisk Milk (3/4 cup), Egg (1) and Vanilla Extract (1/2 teaspoon). Add to flour mixture and mix until combined and no lumps. Pour batter on baking dish. Add the cooked peaches on top.
Bake for 45 to 50 minutes. Allow to cool a little bit. Serve with vanilla ice cream or whipped cream. Yum!!!