In a 9-inch skillet or baking dish, gently combine the peaches and cornstarch.
In a small bowl, combine the flour, brown sugar, baking powder and salt. Sprinkle the mixture over the peaches, and dot with the butter, making sure it is evenly distributed.
Bake at 350F for 45-55 minutes, or until bubbly and golden.
Serve warm with ice cream!
*I prefer peaches peeled in my desserts, but if you don't mind the skin go ahead and leave them!