Simple question -

I want to create a timer in a WP7 application that simply keeps track of how long something has taken. I'll end up displaying this as:

Time: 00:00

With elapsed minutes and seconds. What is the best way to do this within a WP7 app? I'll also want to end up pausing and restarting the counter at times too:

Time: 00:00 (paused)

This should be easy