Marshmallow Fondant

I made some marshmallow fondant. It was pretty easy to follow the Wilton recipe except that they say a bag (16 oz) of mini marshmallows but the bag I had was 10.5 oz. I used my food scale to help out making a half batch instead of a full. I figured why waste food if it doesn't turn out well? My lump of stuff is resting overnight in the fridge. I should have snuck a taste before I put it up ...