You must be in Australia? I have a friend that uses the term mudcake and she is from Australia! I do not have a caramel recipe that I really like so can't help you but would like to see what others have to offer!
Never made one Shaira, but I thought these looked really good -
I have this one http://cakesdecor.com/cakesbyraewyn/blog/181
I haven't made this one yet. I've made dark chocolate, milk chocolate and white chocolate mud cakes though. So easy to make and the best part is that they taste the best about 3 days after baking.