In a small bowl, combine the apple, sugar and water. Divide between two 6-oz. ramekins or custard cups coated with cooking spray.
In a small bowl, combine the flour, brown sugar, cinnamon, nutmeg and salt. Cut in butter until mixture resembles coarse crumbs. Sprinkle over apple mixture. Bake at 375° for 20-25 minutes or until tender. Serve warm with whipped cream if desired.