Preheat oven to 375°F.
1. Spray an 8 x 8 baking dish with nonstick cooking spray. Set aside.
2. In a large bowl, combine peaches, brown sugar, cinnamon, lemon juice, and cornstarch. Mix well.
3. In a small bowl, combine Bisquick, sugar, oats, and milk. Mix with a fork or fingers to make a dry crumble mixture.
4. Pour peach mixture into prepared baking dish and top with crumble mixture. Bake 25 to 30 minutes.
5. To serve, top each serving with whipped topping.
Makes 6 servings.