What you need:
1 cup chilled butter, cut into 1/2 slices
2 cups flour
1/2 cup powdered sugar
pinch of salt
3 cups peeled and chopped apple (I used 5 small/medium ones)
1 3/4 cups flour
1 cup brown sugar
1/4 cup butter, melted
1 teaspoon baking powder
1 teaspoon salt
1-2 teaspoons EACH butterscotch liqueur or creme de cacao (or just use vanilla if that's what you have)
2 cups powdered sugar
2-3 teaspoons ground cinnamon
2-4 tablespoons milk
Start by making the crust:
Measure the flour, powdered sugar, and salt into a mixing bowl. Cut the butter in using a pastry blender until it is evenly distributed and the mixture is crumbly with chunks no bigger than small peas. Or, if you don't have a pastry blender, use forks or even your hands. Chill the mixture for 10 minutes in the freezer (and maybe work cutting up those apples while you are doing this). Heat oven to 400 degrees Fahrenheit. Press crust into two 8x8/ 9x9 pans or one 13x9 pan. Bake for 15 minutes or until VERY lightly browned.
To make the filling:
Mix all of the filling ingredients together. Plop evenly on top of the warm crusts. Reduce oven heat to 350 degrees Fahrenheit. Bake for 20-30 minutes or until golden brown and apples are cooked through. If it is getting too brown at any point, cover with aluminum foil for the remaining baking time.
Mix together glaze ingredients, adding enough milk to make a thick, but completely mixed, glaze. Pour on top of hot apple bars.
Let cool for at least 20 minutes before cutting into if you want to have presentable looking bars. Or just dive in and get 'em while they're hot. They may slop over a bit, but they'll still be delicious. I made 32 small-ish bars out of this. Enjoy!