Preheat oven to 350°F and spray a 9x13 baking pan with non stick baking spray.
In a small bowl, combine graham cracker crumbs and melted butter with a fork, until it looks like sand. mix well. Press the graham cracker crumb mixture firmly into bottom of prepared pan.
Layer the coconut flakes, nuts, chocolate chips and butterscotch chips evenly over the crumb layer.
Pour sweetened condensed milk evenly over the entire pan.
Bake for 25-30 minutes or until lightly browned. Loosen from sides of pan while still warm and let cool before cutting.
Notes
For perfectly cut cookie bars:
Gently remove the entire cookie bar from pan and put onto a cutting board.
Make 4 cuts along the 9" inch side of the pan, giving you 5 rows and then 6 cuts along the 13" side giving you 7 columns.
Make sure your knife is clean by rinsing it in hot water before each cut. The cleaner the knife, the cleaner the slice will be on each cookie bar.
Storing leftover cookie bars
If you want to make hello dolly cookies in advance or just have leftovers (which I never seem to) the steps for storing are the same.
Cut the bars into squares.
Layer them in an airtight container with the layers separated with parchment or wax paper.
Enjoy within 5 days, or put in the freezer for up to 3 months.