I would have read this book in the mid to late 1970s and I am pretty sure it was published around then. It was about a woman who owned a diner, but she was a terrible cook. Her customers all complained about the horrible food — I remember one diner saying, “This tastes like a burnt tire!” Somehow she finds (traps? meets?) a genie who promises to help her. He makes delicious spaghetti and meatballs that everyone loves, but the magic he used to make it goes out of control and fills the diner with spaghetti and meatballs until everyone floats away on a river of pasta. I seem to recall that the illustrations were primarily in black and white with splashes of color. The drawing style was sort of crude and comical — heavy, rough lines and the faces of the characters were somewhat grotesque. The main character’s name could be Frieda? Possibly. Also, this is definitely not Strega Nona which has a similar magical spaghetti pot.