For those who can't, or don't want to, consume marshmallows made with pork gelatin, there are "halal" marshmallows made with beef gelatin. I used these to make rice krispie treats (the wife helped out), and they turned out quite well. It was a big hit at home.
First I melted 2 tablespoons of butter in a saucepan. Then I added 5 ounces of halal marshmallows and mixed until smooth. Then I added 3 cups of Cocoa Krispies cereal and mixed until everything was blended nicely. I also added some chocolate chips (I would say around 1/2 cup, but I didn't measure).
I had a square baking pan prepared with a big piece of wax paper. I scooped the marshmallow/crispie mixture into the pan, and used the wax paper to push down and smooth it out.
After letting it cool, we peeled off the wax paper and cut into squares. Here's a pic...