Preheat oven to 375° and spray a 9 x13 inch baking dish (or similar in size) with a non stick spray. Set aside.
For the Cherry Filling: Add cherries to a large mixing bowl.Sprinkle sugar, brown sugar, lemon juice and cornstarch over cherries, gently stir. Let sit for 5 minutes, then stir again. Pour cherries into prepared baking dish. Set aside.
For the Topping: In a medium mixing bowl, whisk flour, sugar, brown sugar, baking powder and salt together.Using a pastry blender, or a fork, mix butter into flour mixture until crumbly.
Pour water into flour mixture and stir until combinedTop cherries with topping mixture. Sprinkle additional sugar and cinnamon, if desired, on top of batter.
Bake uncovered for 50 minutes or until topping is cooked thoroughly and has started to brown.Serve warm topped with vanilla ice cream.