The argument between the couple began when Julie Evans, 45, allegedly poured water over her husband, James, as he slept on the sofa, the Mirror reported.
She had allegedly asked him to help with chores, and was reportedly still upset the next morning.
"She started an argument and threw her toast at him. He left as he felt she was being petty, but she grabbed a handful of butter and smeared it on his face," prosecutor Theresa Perry said. "He then tried to rub some of it back on her and they ended up on the floor."
James, whose last name wasn't reported, needed 13 stitches to repair a tear in his ear, the Mirror said.
Evans denied the assault and is scheduled to go on trial in July.