Can substitute marshmallow creme instead of marshmallows.
There are a couple of "secrets" to making the perfect gooey Rice Krispie Treats: (1) the stovetop is THE way to go (the pan washes out easy w/hot soapy water) (2) you HAVE to melt the butter sloooowly and make sure it doesn't turn brown at all. (3) mix in the marshmallows and melt them just as slowly. If the butter gets brown, the treats will be dry. We double our recipe and it still fits fine into a 13x9 pan (grease the pan w/butter). To make them truly gooey use the following measurements: 11.5 cups Rice Krispies, 1 whole stick of butter, (1) 16oz bag of mini marshmallows. (I always use Jet Puff brand). I've become the neighborhood "treat" maker because the neighbors say theirs never turn out like mine. - 24 Mar 2008 (Review from Allrecipes US | Canada)
ADD 2 1/2 TEASPOONS OF MILK WHEN THE MARSHMELLOWS ARE ALMOST DONE MELTING AND IT MAKES IT GOOIER AND CREAMIER!!! - 24 Dec 2007 (Review from Allrecipes US | Canada)
These are great!! I went a little crazy throwing stuff into them, lol. I added a few chocolate chips I had left from another recipe, a couple Hershey bars broken up, and a big spoonful of peanut butter. Yum! I didn't butter the pan, I used cooking spray. Another helpful tip, if you spray your hands with the cooking spray, you can press them into the pan without getting all sticky! - 27 Apr 2008 (Review from Allrecipes US | Canada)