1. Preheat oven to 350°. Toss chopped apples with lemon juice in a medium bowl. Add brown sugar, stirring well to coat.
2. Whisk together pancake-and-waffle mix, granulated sugar, and cinnamon in a medium bowl; stir in milk, butter, and vanilla. Fold apple mixture and any accumulated juices into batter. Spread into a lightly greased 8-inch square pan.
3. Microwave apple juice in a 2-cup glass measuring cup at HIGH 2 to 3 minutes or until boiling. Using a spoon, gently drizzle hot apple juice over batter in pan. (Some batter may float once juice is added.)
4. Bake at 350° for 30 to 35 minutes or until a cake layer forms on top and layer springs back when touched. Let cool on a wire rack 25 minutes. Serve warm with ice cream, if desired.
Note: For testing purposes only, we used Aunt Jemina's Original Complete Pancake And Waffle Mix.