While Theron admires Harrelson's commitment to living a vegetarian, eco-friendly existence; she couldn't resist taking the opportunity to poke fun at the actor.
She says, "He's really somebody to look up to. He's very disciplined when it comes to saving the environment and being respectful and healthy, which just makes me want to make fun of him all the more.
"I like to eat meat, but around Woody, for some reason I loved eating meat. He's organic and he doesn't cook food, he eats raw food only. And if he cooks food it takes about four years, because it can only go to a certain temperature. So he makes cookies five years in advance. It's like a light bulb cooking it.
"He drives the hybrid cars and things like that - which we should all do - but it's great to fly somewhere with him and get off plane and go, 'How does it feel Woody? All of that pollution!' It just kills him, it just absolutely drives him insane.
"But I am on his side of the issue, for sure. He's doing a good thing and we should all do that. But baking cookies for four years, that's not my thing."