Be polite, smile, say "no thanks I will do it my way" and escort her out of the kitchen, "isn't Jeopardy on". Or find a task just for her ( you make the salad). Or you can start world war III by saying FINE YOU DO IT.

I had a aunt in law that was like this, looking for all the dust, know it all in the kitchen.
She had a freak out because I roast my turkeys upside down. She was going completely ballistic ( politely) about it when I got a call from a friend wanting to know how I did the "most delicious turkey ever". My friend got a kick out of it, he said I bet you wish you had a speaker phone.

I would not sit there, you are not in the entertainment business. Do whatever you need to do just be nice about it. "I have to go fold 17 loads of laundry, I will be in the basement". That puts the ball in her court. She can come help you and chat you up, or sit there, her choice. Same thing, go to the grocery, who knows maybe she'll pick up the bill.