There are lots of posts on cleaning granite here:
I clean mine with a granite wipes then twice a year I clean it let it dry and seal it - here is more info for you
The trouble with granite is that it is porous. If you have left spills sit, they can permanently damage the granite. For really tough, dried on spots, I use warm water with dishsoap and let it sit on the granite for a couple of minutes to lift the spots. Then using a soft cloth, I wipe it dry. Repeat until it has all come off, then buff it with a dry cloth.