Preheat oven to 350F. Line an 8-by-8-inch baking pan with aluminum foil, spray with cooking spray. Don’t skip lining the pan with foil because bars are sticky.

Combine flour & brown sugar in a large bowl. Cut in the butter using two forks or a pastry cutter. Keep working until butter is evenly distributed and pea-sized lumps and sandy bits form. The softer the butter is, the quicker and easier it is. If you use firm butter you can grate it with your large grater before adding.

Turn mixture out into prepared pan and pack it down to form a smooth, even crust.

Bake for 17 to 18 minutes, or until crust is just set. Don’t overbake because pan is going back into the oven after filling is added. While crust bakes, prepare the filling.

Combine the egg, brown sugar, maple syrup, vanilla, salt in a large bowl. Stir in the pecans.

Carefully pour filling over baked crust (give filling one last quick stir before pouring it), smoothing & evenly distributing the pecans.  Make sure they’re not clustered in one area and they’re as flat as possible to minimize the chance of burning.

Bake for about 16 to 19 minutes, or until center is set and not jiggly. The bars will set up more as they cool. 

Place pan on a wire rack to cool for at least 1 hour before drizzling with salted caramel (if desired) and slicing. Bars will keep airtight at room temperature for up to 5 days, or in the freezer for up to 6 months.