Preheat oven to 375°F. Butter a 2-quart baking dish; set aside.
Combine apple slices and lemon juice in large bowl; toss until apples are coated with juice. Add apples to large saucepan and add remaining filling ingredients. Cook over medium-high heat, stirring frequently until mixture comes together and creates a syrup that coats the apples (about 5-7 minutes). Pour apple mixture into prepared dish.
Combine flour, sugar, baking powder and salt in large bowl; whisk together until incorporated. Add butter, egg and milk; stir well. Drop spoonfuls of batter on top of apple mixture and spread it slightly using the back of a spoon. Generously sprinkle with coarse sugar. Bake 35-40 minutes or until apples are tender and crust is golden brown. Serve warm with a scoop of ice cream.
Notes
*If you don’t have apple pie spice, you can use 1 teaspoon each cinnamon, nutmeg and ground ginger.