The short answer is, 2 including a full against the grain pass.

I skip most of the first pass and some of the second. My beard is light enough that most of it gets an across the grain pass to start and only some of it gets a with the grain start. The whole thing gets the against the grain pass as it needs it because too many of those hairs just lie so flat against my face that the only way to get a close shave is to come underneath them.

X