Ice cream or whipped cream, for serving (optional)
Preheat oven to 375°F.
Place the butter in a 13×9-inch baking dish. Place in oven until the butter melts, about 5 minutes. Remove from oven and set aside.
In a large mixing bowl, combine the flour, 1 cup of sugar, baking powder, and salt. Stir in milk just until the dry ingredients are moistened. Pour the batter over the butter in the baking dish. Do NOT stir.
In a separate large mixing bowl, combine the remaining 1 cup of sugar with the peach slices, and lemon juice. Mix well. Pour the peach mixture over the batter in the baking dish. Do NOT stir. If desired, sprinkle with cinnamon.
Bake for 40-45 minutes or until the cobbler is golden brown.