Preheat the oven to 350°F.
Place the butter in a 9 x 12" oven-safe baking dish. Heat the butter in the oven until it's melted.
In a medium bowl, mix the flour and 1 cup sugar.
Slowly add milk and continually stir to keep the batter from lumping.
Carefully remove the hot baking dish from the oven, and pour the batter directly over butter in the dish. Do NOT stir.
Spoon your fruit on top of the batter, then gently pour the syrup (or reserved syrup from canned peaches) on top. Do NOT stir.
Optional - If desired, sprinkle cinnamon on top of batter. Do NOT stir.
Bake in the oven for 30-45 minutes or until golden brown. The batter will rise above the fruit and create a delicious crust.
Serve warm with vanilla ice cream or fresh, homemade whipped cream.