i had a picky female that i had to trick into eating rats because she was overly fond of mice.
not sure if you can do it the exact same way as i did, but if you feed live, put a mouse and a rat in her enclosure at the same time. as soon as she goes into what i refer to as "hunt mode", remove the mouse. she should still go after the rat.
I've never heard of that one before, will have to try it!