The radiation left over from the Big Bang is the same as that in your microwave oven but very much less powerful. It would heat your pizza only to minus 271.3*C - not much good for defrosting the pizza let alone cooking it.
I think it's a tough road if you're a stay-at-home mom a working mom if you have a partner if you don't. It's the best job in the world and the toughest job in the world all at the same time.
