Prepare pan by lining an 11X7-inch baking dish with foil, allowing excess foil to hang over pan edges. If you want the treats thinner, use a 9X13 – for thicker treats still use an 8X8-inch pan. I found the 11X7 pan size to be perfect – not too thick and not too thin. Grease the foil with nonstick cooking spray.
Melt butter in a large pot over low heat. Add marshmallows, white chocolate chips, and salt and cook, stirring constantly, until melted and smooth, about 8 minutes. Stir in vanilla.
Off heat, stir in rice krispies and cherries or cranberries until incorporated. Scrape mixture into prepared pan and press into bottom and corners with a greased spatula (I just used my fingers since the marshmallows weren’t overly hot at this point). Let cool completely, about 1 hour.
Melt semisweet chocolate chips in the microwave on low at 30 second intervals until smooth. Pour melted chocolate into a ziploc baggie, pressing chocolate into one corner of the bag. Using scissors, clip a tiny piece off the corner and drizzle chocolate over cooled treats. Allow chocolate to cool, about 45 minutes. Using foil overhang, lift treats from pan. Cut into squares. Serve.
Double Chocolate Caramel Turtle Treats: prepare crispy chocolate cherry treats, substituting 1/2 cup semisweet chocolate chips for white chocolate chips. Omit the cherries or cranberries and stir in 15 soft caramel candies, quartered, and 1 cup chopped toasted pecans with the rice krispies.Fluffer-Nutter Treats:prepare crispy chocolate cherry treats, substituting 1/2 cup peanut butter chips for white chocolate chips, 1 cup dry-roasted peanuts for dried cherries or cranberries, and 1/2 cup peanut butter chips for semisweet chocolate chips.