2 cups all-purpose flour
1/2 cup granulated sugar
1 cup unsalted butter
6 tbsp melted unsalted butter
6 eggs, lightly beaten
3 cups packed brown sugar
6 tbsp all-purpose flour
1 1/2 tsp baking powder
2 tsp pure vanilla extract
1 1/2 cups coarsely chopped pecans
Preheat oven to 350F
Spray a 9 x 13 baking pan with cooking spray and line with parchment paper. Make sure there is an overhang of paper to allow for removing from pan after baked.
In medium bowl, combine flour and granulated sugar, cutting in butter with pastry blender until crumbly. Press into pan and bake for 15 minutes (or until very light golden brown on edges).
In bowl, mix melted butter and eggs, blending in brown sugar, flour, baking powder, vanilla, and salt. Stir in pecans and pour over base.
Bake for 20-25 minutes until top springs back when lightly touched. *It should not feel firm--it's really important that you don't overbake, or they won't be "ooey gooey."
Let cool on rack, then cover and refrigerate until very firm. Using the parchment overhang, remove from baking pan and place on cutting board. Cut into squares.
Keep refrigerated until about an hour before you need them, if you can (they get really gooey otherwise, which isn't necessarily a bad thing). They can also be frozen (and they really do taste delicious right out of the freezer!).