In a medium bowl, mix 1 cup flour, ⅓ cup white sugar, brown sugar, cinnamon, salt, and ginger if using. Add the cold butter cubes and use a pastry cutter to blend until the mixture forms large pea-sized crumbs, about 3 to 4 minutes. Place this crumble topping in the fridge while you prepare the apples.
In a 2-quart baking dish, toss the sliced apples with ¼ cup sugar, 2 tablespoons flour, and cinnamon until well coated.
Spread the prepared crumble topping evenly over the apple mixture.
Bake uncovered for 35-40 minutes, or until the topping is golden and the apples are tender.
Serve warm or at room temperature, with vanilla ice cream if desired.