Sneak Peek: Dining with the World’s Heaviest Mom

New Jersey mom Donna Simpson is in the Guinness Book of World Records as the world's heaviest mom -- and she wants to keep gaining weight. Tonight, she shows ET what she eats in order to expand her substantial size.

A mom-of-two, Simpson was awarded the Guinness title when she weighed in at over 500 pounds when she gave birth to daughter Jacqueline. Now she is about 600 pounds and wants to keep gaining. She shares what she eats for a typical super-sized breakfast in our sneak-peek video.

Tune in to ET tonight for more.