I need to make an M&M for the cake topper for the Grooms cake. Does anyone know how to make one? Or out of Rice Krispy Treats? I can't find anything online or on CC.

I think the best thing for you to use is rkt and mold into and m&m shape or try baking in a ball pan and carving it.

I agree with caramelchef. I think if you 're doing a topper you want something a little lighter so RKT would be your best bet. Cover in fondant and make the arms and legs out of gum paste (if you want the arms and legs that is).