I suspect she's doing all this partly because she likes being "behind the scenes" and can't stand to just sit around while someone else is doing the work. I suggest you have something in another room you can "assign" her to do - entertaining kids, chopping vegetables, making sure nobody needs a drink, etc. It won't solve everything but it will probably help.
I also wouldn't make any referernce to sabotoge, even in jest - I guarantee you she doesn't see her past actions in those terms, even if that's effectively what she was doing. Alluding to sabotoge will only make her defensive and even MORE determined to be "helpful" in the kitchen, to prove you wrong.