Competency Based Interviewing. As distinct from traditional interviewing, it is a rather structured interviewing process that focuses on gathering actual examples of behavior in given situations, from the recent past, through appropriate questioning using the STAR technique:
Situation - what was the situation in which you found yourself, when, and who was involved?
Task - what the specific task which you had to achieve?
Action - what action did you take, what did you do/say, why, what was your role?
Result - what the outcome, how did you know, what did you learn, why, how?
In preparing, I suggest you start thinking about your experiences - such that involved decision making, time management, leading others, team work, etc.
Word of Advice: BE ABSOLUTELY CONFIDENT; show em you've got what it takes to be a P&Ger!
Good luck!