Preheat oven to 375 degrees F and grease an 8x8 square baking dish.
Prepare the filling: In a large bowl, add the sliced peaches, white sugar, lemon juice, cornstarch, vanilla, and salt. Toss until well coated and pour into prepared pan.
For the Topping: In a medium bowl, add the flour, brown sugar, oats, butter, baking powder, cinnamon, and salt. Mix together with a pastry cutter, fork or use clean hands to make sure the topping is well combined. Sprinkle over the peach filling.
Bake for 30-35 minutes or until topping is golden brown and crisp. Serve with a scoop of vanilla ice cream.