Why don my rice krispie treats stay soft?
It has to do with how hot the heat is when you melt the marshmallows. I don’t know why this happens but I know from experience that if you have the heat too high when you’re melting the marshmallows they get to hot and it changes them in some way. I always use name brand, fresh marshmallows, regular margarine (not light), and store brand rice krispy cereal but sometimes it’s turned out all hard like you said. The only difference is that I had the heat up when melting the marshmallows so I figured that has to be it. I tried it again being careful to keep the heat down and take it slow, they turned out nice and soft.