For the crust
Preheat oven to 300 degrees.
Line an 8-inch pan with parchment paper.
In a large bowl, combine 1/2 cup butter, 1/4 cup sugar and 1/4 teaspoon salt. Mix in 1 cup flour until just combined.
Press mix into the pan. Place in freezer for 10 minutes, then in the oven for 25 to 30 minutes, until golden brown.
For the apple layer
While the crust bakes, combine apples, 2 tablespoons flour, 2 tablespoons sugar, 1/2 teaspoon cinnamon, 1/4 teaspoon of the five spice powder and a pinch of salt in a bowl and set aside to crumble top.
For the pecan crumble
In a bowl, whisk together 1/2 cup flour, pecans, 1/3 cup brown sugar, remaining 1/4 teaspoon five spice powder, 1/8 teaspoon cinnamon and pinch salt. Use your fingertips to work the cold butter into the mix until it starts to clump up into coarse crumbs. Place in the refrigerator until ready to use.
To assemble
Turn the oven temperature up to 350 degrees.
Layer the apples on the hot crust, pressing down evenly. Top with the crumble and bake 30 to 35 minutes or until the apples are tender and bubbling and the crumble is golden brown.
Remove from oven and let cool completely before slicing into bars.