Chewy Caramel Popcorn and Pretzel Bars

I just have a few things to mention about this recipe.  First, it is featured in the current issue of my friend Martha's Everyday Food, which you should probably subscribe to.  Second, I added Reese's Pieces, because, in my opinion, Reese's Pieces make everything better.  Third, I was a little "meh" about them, but then found that I couldn't stop eating them, so I guess I was a more "mmmmm!" than "meh."  When I took them to school to have my coworkers and students finish them off, they were all "mmmmmmmmm!"

So, anyway, here goes it.

Chewy Caramel Popcorn and Pretzel Bars (from Martha Stewart's Everyday Food, October 2010)

Ingredients
Nonstick cooking spray
12 cups plain popped popcorn (from 1/2 cup kernals or 2 microwave packages)
4 cups coarsely chopped small salted pretzels

2 cups sugar

coarse salt

2/3 cup heavy cream

2 cups miniature marshmallows

Directions

1. Coat a 9 x 13" baking dish with cooking spray.  In a large bowl, toss together popcorn and pretzels.  In a medium saucepan, bring sugar, 1/2 teaspoon salt, and 1/2 cup water to a boil over medium high.  Boil, undisturbed, until mixture is amber in color--8-12 minutes.  Remove pan from heat and slowly pour in cream (mixture will sputter).  Immediately add marshmallows; stir until melted.

2. Pour caramel mixture over popcorn and pretzels and quickly stir with a rubber spatula to coat.  Transfer mixture to dish and use a piece of plastic wrap coated with cooking spray to press evenly into dish.  Sprinkle with coarse salt if desired.  Let cool completely before cutting into bars.

**Note: I made half with Reese's Pieces and half without.  People overwhelmingly preferred the Reese's Pieces variety.