1. Preheat the oven to 350 F (180 C).  Butter a 13 x 9 pan and then line the sides and bottom of the pan with a piece of parchment.

Streusel

1. Melt the butter in a small pan.
2. Mix the flour, brown sugar, apple pie spice and a pinch of salt in a large bowl.  Pour the butter over the flour mix and then stir to form large crumbs.
3. Pour a little more than half of the streusel in the bottom of the baking pan.  You don’t need to be precise here; you just need enough to cover the bottom of the pan.  Use your knuckles to press the streusel into a thin even layer of crust.  You should not be able to see any crumbles if you did a good job on this step.
4. Bake the crust for 7 minutes.  You don’t need the crust to be brown, but baking it a little will help the apple juices from making the crust soggy later.  Set the crust aside to cool.
5. Stir around the bottom of the bowl to make sure that the streusel is mixed well.  Put the bowl in the freezer while you prep everything else.

Apples

1. Wash and peel your apples.
2. Slice just to the right of the core on all 4 sides of an apple. From there, lay the apple pieces flat on your board and cut thin 1/16″ slices. Thin slices will lay pretty on top the crust and bake perfectly during the specified cooking time.
3. Mix the sugar, flour, and apple pie spice for the apples.  Sprinkle this and the apple butter over the apple slices.  Use your hands to mix everything together until the apples are coated with the apple butter and the flour mix.
4. Pile the apples on top of the crust.  Bake for 20 minutes.
5. After 20 minutes, take the apples out of the oven.  Scatter the frozen streusel over the top of the apples.  Bake for 30-35 minutes, until the streusel is lightly brown and crisp and the apples are tender.
6. Cool the bars for about an hour before you try to cut them.  To cut, pull on the sides of the parchment, placing them on a cutting board.  Cut into 15 pieces.
7. Serve the bars warm with a scoop of ice cream or a drizzle of heavy cream. 
8. These easy apple pie bars will keep well at room temperature for up to 2 days or up to a week in the fridge.  You can use my Mom’s trick of storing them in the oven, loosely covered with foil.  Just be sure you remember they’re there!