My pick, hands-down and in a heartbeat, would be dishes and kitchen clean up after every meal. Whenever my mother or mother-in-law stays with us and takes this duty over, it's a small taste of heaven for me.
I once read that spouses are encouraged to write down the list of regular chores and assign each a number of 1-10 (one being least favorite). Then you could see if one of your #1's is one of your hubby's #10's (or somewhere close). Then you could see if he would be willing to do it
So kitchen clean up is my #1. (Honey, are you reading this?). :)
What is your least favorite?