Ever since I have been back in my element, expressions I have not used for so long have been coming out of my mouth, one of them being QUE LECHE!.
Que leche would literally mean What milk! but the idiomatic meaning is What luck! or Que mala leche! What bad luck!
I think I recently used it when I was talking to Walter my cousin`s husband about his travels through Mexico and how much leche you need to have to come out with no major incidents.