The Book of Unknown Americans discussion

I'm looking for the name of an Avalon Romance book I read mid-90s. A girl has no job goes to eat at a restaurant and can't pay for it. Tries to put a fly in her soup. Ends up saving a man from choking. He hires her to be a nanny for his two kids. Their uncle is a bad guy. She is a gymnast and saves the kids by walking along a beam and dropping down on the bad guy.