3/4 cup (6oz/ 170g) unsalted butter, softened to room temperature
1/2 cup (3 1/2oz/ 99g) packed soft brown sugar (preferably light but dark is fine)
2 cups (8 1/2oz/ 240g) all purpose flour
1/4 teaspoon plus 1/8 teaspoon salt
FOR THE PECAN TOPPING:
1/2 cup (4oz/113g) unsalted butter
1 cup (7oz/199g) packed brown sugar (preferably light but dark is fine)
1/3 cup honey (*see not for substitution)
2 tablespoons heavy whipping cream
1/8 teaspoon salt
2 cups (8oz/ 227g) coarsely chopped pecans
TO MAKE THE SHORTBREAD CRUST:
Adjust oven rack to middle position and preheat oven to 350F/180C.
Line a 13 X 9-inch baking dish with a large sheet foil, leaving a two-inch overhang on all sides. Spray foil with a non-stick cooking spray.
In the bowl of a stand mixer fitted with a paddle attachment (or a medium bowl and an electric hand mixer) beat the butter on medium-high speed until soft and ribbon-like; about 1 minute. Add in the brown sugar and salt and beat together until lightened in both texture and color; 3 to 5 minutes.
Turn down the mixer to lowest speed, then gradually add in the flour and mix until dough comes together in crumbles.
Press the dough into the prepared baking dish, then using the back of a measuring cup, smooth out into an even layer.
Bake for 20 minutes, or until golden brown. While the crust bakes, make the pecan filling.
TO MAKE THE PECAN FILLING:
In a medium saucepan set over medium heat, melt together the butter, brown sugar, honey, heavy cream and salt. Bring mixture to a simmer then allow to simmer for exactly 1 minute. Don’t overcook or the filling will be harden and become candy-like instead of soft and stretchy. Stir in the pecans.
Take the shortbread crust out of the oven, then pour the pecan mixture over the hot shortbread and spread into an even layer.
Return the baking dish to the oven and bake again until the top is bubbling; 12-18 minutes. Be sure to take it out of the oven as soon as the surface bubbles all over and no just around the edges. If you bake it beyond bubbling, the filling will not be as soft and chewy; so make sure not to overbake. The filling will still look liquidy, but will set up upon cooling.
Allow to cool completely in the pan. If you’re in a rush, you could speed up the cooling process by placing the pan in the fridge or freezer. Then, using the foil overhang lift the bars out of the pan and place on a cutting board. Slide the foil from underneath the bars and discard, then cut into 16 bars; 4 rows by 4 rows. Store in an airtight container at room temperature for up to 5 days.