In a large mixing bowl, toss sliced apples in lemon juice. Mix in brown sugar, cinnamon, nutmeg, ginger, and salt.
Spread the apples in a square baking pan. Mix vanilla extract and maple syrup and pour over the apples.
Dot with butter pieces.
Top with pie crust, tucking the sides down if there is any overhang.
For a sparkly crust appearance, brush crust with milk and sprinkle with coarse sugar.
Bake for 30-35 minutes or until the crust is lightly browned. Cut the crust into 9-12 squares. Push each square into the filling.
Reduce the oven to 350 F, return the pan to the oven, and bake for 30 more minutes or until the crust is nicely browned.