Preheat the oven to 350
Make the crust by mixing the flour, 1 cup of brown sugar , the ½ cup of melted butter and the pinch of kosher salt together in a medium sized bowl.
Press this mixture into a 9x 13 baking dish.
Sprinkle the chopped pecans around evenly over the top.
In a saucepan on the stovetop over medium heat, melt the 1 Cup of butter and the ¾ Cup of brown sugar until it comes to a low boil. Boil like this for 1 minute stirring constantly. Pour this mixture over the crust and pecans. Bake for 20-25 minutes.
Remove from the oven and sprinkle quickly and immediately with the chocolate chips. Use a small rubber spatula to gently swirl the chocolate chips to give that marbled appearance.
Cool to room temp (this will take hours) before cutting to eat.