Preheat oven to 375 and grease an 11" round baking dish with nonstick cooking spray.
Add peaches to the pan, including juice and spread into a single layer.
In a mixing bowl, combine cake mix, brown sugar, and cinnamon and mix well. Add melted butter and mix well until crumbly. Crumble topping on peaches and bake for 35-40 minutes until top is browned and edges are bubbly.
Remove from oven and cool until warm. Serve warm with vanilla ice cream.