Line a 9x13 pan with foil, be sure to leave an overhang so that you can easily remove bars from the pan.
Place one layer of crackers in the bottom of the pan. Be sure to cover the entire pan, cut or use broken crackers to fill in any gaps along the edge.
In a medium saucepan, melt butter. Stir in graham cracker crumbs, brown sugar, milk and granulated sugar. Bring to a boil over medium high heat. Stir frequently and boil for 5 minutes.
Pour half of caramel mixture over 1st cracker layer. Cover with another even layer of crackers. Spread remaining caramel over that and add another layer of crackers.
In a small saucepan, combine peanut butter, chocolate chips and butterscotch chips. Melt over low heat until smooth. Pour over top cracker layer and spread evenly.
Chill for at least 1 hour before cutting.
Recipe by Crumbs and Chaos at http://www.crumbsandchaos.dreamhosters.com/2015/11/caramel-crunch-bars/