Criminally Insane 2 (1987)

Fatty, fatty 4X4, can't get in the kitchen door!

A mental hospital, faced with a severe decrease in funding, is forced to release mass-murderer Ethel Janowski into a halfway house. Ethel is psychotic, delusional and has a hefty appetite. In fact, her killing spree began 13 years before with the murder of her grandmother, who had forced her to go on a diet. Now that she's tasted the home-cooked fare at the halfway house, she'll do absolutely anything to get more.